Basic Tips: How Do I Start Programming Deep Brain Stimulation in Parkinson Disease Patients?

ABSTRACT

Deep brain stimulation (DBS) has become an integral component of Parkinson disease treatment. Programming a DBS device is a time‐consuming process and requires a highly trained specialist to obtain optimal results. During the last few years, we have witnessed a rapid technological advance of DBS systems, making the programming process even more complex and emphasizing the need for a structured approach. In this manuscript and the attached videos, we will demonstrate a step‐by‐step programming approach for DBS targeting the subthalamus and the globus pallidus pars Interna. In doing so we will show the main features and differences of the three main systems available on the market, including the newest ones able to record braingenerated local field potentials for clinical applications.

Deep brain stimulation (DBS) is a well‐established treatment for Parkinson disease (PD). There are two main targets that have been shown to improve PD‐related cardinal symptoms: subthalamic nucleus (STN) and globus pallidus pars interna, while ventral intermediate nucleus of the thalamus is beneficial for tremor only.

DBS programming requires specialized, highly trained specialists and it is a complex process taking place over period of a few month. ¹ , ² Although practices vary among institutions, initial programming is usually conducted a few weeks after the surgery when the “microlesional effect” is resolved.

Prior to initiating programming, checking electrode placement on the post‐operative images can exclude complications and envisage potential side effects. Next, checking the contact impedance is warranted to establish the integrity of implanted hardware. Then, the therapeutic window is established in monopolar configuration by increasing the amplitude for each contact (or “level”) while keeping the pulse width (60 μsec) and frequency (130 Hz) constant. Rigidity is the most useful symptoms to assess during the programming as it does not fluctuate and readily changes with amplitude manipulation (Video 1). Finally, the contact with the widest therapeutic window is chosen for chronic stimulation usually starting at 1–1.5 mA. After initiating chronic stimulation, it is recommended to assess patient's axial symptoms as well as development of bothersome dyskinesia after taking antiparkinsonian medications. Stimulation will be gradually increased over the following 4–6 weeks while reducing medications, usually possible with STN (Video 2).

Video 1.

Basic principles and initial steps of Deep Brain stimulation programming for Parkinson's disease.

Video 2.

Overview of Deep Brain Stimulation optimization after the initial programming for Parkinson's disease.

During the last few years, there been a rapid technological advance in the DBS systems providing the clinicians with additional, more flexible programming strategies (Fig. 1, Table 1). ³ , ⁴ These advances have come with a price: programming has become even more complex, ⁵ emphasizing even more the need for a structured approach (Table 2).

FIG. 1.

(A) Common electrode configurations. In unipolar configuration the implantable pulse generator (IPG) serves as an anode while one of the contacts is the cathode. In bipolar configuration both the cathode and the anode are located on the electrode. In double unipolar configuration two or more contacts on the electrode set as a cathode. Interleaving or multi set stim configuration allows activation of two separate programs in an alternating fashion through a single electrode. (B) Special configurations of stimulation. Virtual contact allows to shift the center of stimulation between contacts. Anodal block can be used on a directional lead with placing one or two cathodes and one anode on the same stimulation level allowing shift of the stimulation toward the cathode contacts. In anodic stimulation the IPG serves as a cathode and one or more contact set as an anode. In semi‐bipolar stimulation the anode is divided between the IPG and another contact on the electrode. (C) Contacts nomenclature. Note the different nomenclature used to identify the contacts on the different electrodes available on the market.

TABLE 1.

Technical features of currently used IPGs

System	No. of channels	Vol. (cm2)	RC	Output	Freq. range (Hz)	Indep. Freq.	PW (μs)	Temporal fractionation	Current fractionation	Directional lead	MRI safety	Remote progr.	Brain Sensing
Abbott (St. Jude Medical) Infinity
5	2	30.4	No	mA	2–240	Yes a	20–500	MSS	CA	Yes	C	No b	No
7	2	38.6	No	mA	2–240	Yes a	20–500	MSS	CA	Yes	C	No b	No
Boston Scientific Vercise
PC	2	33.0	No	mA	2–255	Yes	20–450	A	MICC	Yes	U	No	No
RC	2	22.7	Yes	mA	2–255	Yes	20–450	A	MICC	No	U	No	No
Gevia	2	19.8	Yes	mA	2–255	Yes	20–450	A	MICC	Yes	C	No	No
Genus P16	2	34.9	No	mA	2–255	Yes	20–450	A	MICC	Yes	C	No	No
Genus R16	2	20.1	Yes	mA	2–255	Yes	20–450	A	MICC	Yes	C	No	No
Medtronic
Activa SC	1	27.0	No	V/mA	3–250	No	60–450	IL	No	No	C	No	No
Activa PC	2	37.0	No	V/mA	2–250	No	60–450	IL	No	No	C	No	No
Activa RC	2	22.0	Yes	V/mA	2–250	No	60–450	IL	No	No	C	No	No
Percept PC	2	33.0	No	mA	2–250	No	20–450	IL	No	No	C	No	Yes

Abbreviations: A, Areas; C, conditional; CA, coactivation; Freq, frequency; IL, interleaving; indep, independent; IPG, implantable pulse generator; MICC, multiple independent current control; MSS, multi system set; PC, primary cell; prog, programming; PW, pulse width; RC, rechargeable; U, unsafe; Vol, volume (modified from 3).

^aOnly between leads/hemispheres.

^bUnder investigation.

TABLE 2.

Step‐by‐step programming of STN and GPi DBS for PD as detailed in the accompanying video

1	Assess patient's baseline condition by using the motor section of the UPDRS.
2	Check post‐operative MRI or CT to confirm electrode placement and exclude surgical complications. Evaluate the symmetry and placements of electrode placement to envisage potential side effects.
3	Perform the initial set up of the IPG. This includes inserting information regarding patient's and physician's name, diagnosis, type of electrode, brain target, side of each electrode and IPG location.
4	Check contact impedance for each possible combination to exclude hardware problems.
5	Set the baseline stimulation parameters as follows: IPG as anode (+), one electrode contact as cathode (‐), pulse width at 60 μsec, and frequency at 130 Hz.
6	Assess rigidity level by level using 0.5 mA or V increments. Rigidity readily changes with manipulating the amplitude while bradykinesia needs more time to improve. Note that tremor tends to fluctuate and worsen with anxiety, however it can improve during programming. One or more virtual contact(s) can be tested if time and IPG allow (see video for details). From time to time, pretend to change stimulation to assess patient's placebo/nocebo response. Avoid asking too many questions during the programming to reduce the anxiety and nocebo effect. Avoid long assessments to maximize the efficiency of the visit and reduce fatigue.
7	In case of directional DBS: Directional DBS can be implemented during the initial programming or later during the optimization phase. There are two methods to identify the best segmented contacts: Assessing rigidity contact by contact using 0.25mA increments (Abbott and Boston Scientific systems) Horizontal steering (Boston Scientific system)
8	LFP‐guided approach using the “Brain Survey” of Percept IPG (Medtronic): LFP activity in the beta band correlates to motor severity of PD. The closest contact to the beta source is theoretically the most effective for chronic stimulation.
9	Select the best contact(s) for chronic stimulation. Start chronic stimulation at low settings (usually 1‐1.5mA/V). Assess the effect of stimulation on axial symptoms after ~30 min. Assess the patient after the first dose of L‐dopa to exclude bothersome dyskinesia and anti‐kinetic effect of DBS.
10	Educate the patient about the use of the remote control: turning OFF the stimulation in case of bothersome side effects; consider providing patient with stimulation limits.
11	The optimization process involves slow adjustments over 4‐6 weeks. Stimulation will be increased slowly while decreasing medications. Further optimization process will involve: Shaping the VPA by means of temporal fractionation, current fractionation, and/or directional stimulation. Engaging different neuronal networks by manipulating the pulse width and/or frequency.
12	LFP‐based PD diary using the “events” function of Percept IPG (Medtronic): Up to four events can be set and personalized based on patient's needs and clinical features. An accurate LFP recording will be triggered by the patients using the dedicated remote control. These recordings will be reviewed and filtered later on by the treating clinician.

Abbreviations: CT, computer tomography, DBS, deep brain stimulation, GPi, globus pallidus pars interna, IPG, implantable pulse generator, LFP, local field potentials, MRI, magnetic resonance imaging, PD, Parkinson disease, STN, subthalamic nucleus, UPDRS, Unified PD Rating Scale, VTA, volume of tissue activated.

Author Roles

(1) Research project: A. Conception, B. Organization, C. Execution; (2) Statistical Analysis: A. Design, B. Execution, C. Review and Critique; (3) Manuscript: A. Writing of the first draft, B. Review and Critique.

C.G.: 1C,3A

A.F.: 1A, 1B, 3B

Disclosures

Ethical Compliance and Statement

The authors confirm that the approval of institutional review board was not required for this work. Informed consent was separately obtained for all videotapes taken. We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines.

Funding Sources and Conflicts of Interest

This study was funded by the University of Toronto and University health Network Chair in Neuromodulation and Multidisciplinary Care to AF. AF received honoraria and research support and honoraria from Abbott, Boston Scientific, Brainlab, Ceregate, Inbrain and Medtronic.

Financial Disclosures for Previous 12 Months

CG has nothing to disclose. Dr. Alfonso Fasano received honoraria and/or research support from: Abbott, Abbvie, American Academy of Neurology, Apple, Brainlab, Boston Scientific, Huawei, Inbrain, International Parkinson and Movement Disorder Society, Ipsen, Medtronic, Paladin Lab, Springer, Sunovion, UCB pharma, University of Toronto.