A modeling study on test stimulation during deep brain stimulation lead implantation

A modeling study on test stimulation during deep brain stimulation lead implantation.

Background and problem statement

Parkinson’s disease (PD) is a movement disorder characterized by tremor, muscle rigidity, slowing and loss of physical movement and balance problems. A treatment method for this disease is deep brain stimulation

(DBS). This therapy involves implanting a lead consisting of four cylindrical electrodes (Figure 1a) in the subthalamic nucleus (STN). Through one, or a combination, of the four electrodes high frequency electric pulses are delivered to the STN. The clinical outcome highly depends on the location of the electrodes within the brain. Therefore, the correct placement of the stimulation lead is extremely important during surgery.

Before surgery, the coordinates of the STN are predetermined in a patient specific brain atlas, based on the patient’s MRI images and a stereotactic frame. During surgery, 3-5 test electrodes (micro-macro tip lead) are placed near the predetermined target coordinate and a test stimulations procedure is performed with these electrodes. The procedure requires that the patient is awake and is used to confirm symptomatic improvement and side effects. The location with the best clinical window (best symptomatic improvement and least side effects) is designated as the final location for the DBS lead.

A new generation of stimulation electrodes is developed by Sapiens (Sapiens Steering Brain Stimulation BV, Eindhoven, nl ) consisting of 64 instead of four contacts (Figure 1b). The advantage of this new high resolution lead is the ability to steer the direction of the stimulation field. However, having 64 contact points also increases the complexity of selecting the right stimulation settings. Therefore, new methods needs to be developed to aid the physician in this complex task.

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Figure 1, The Medtronic DBS lead (A) and the Sapiens high resolutions DBS lead.

Assignment

In this project you will develop a computational model, which is able to visualize the stimulation effects of the test procedure with the micro-macro tip electrode. This model can be a sub-model of the already existing model which includes the Sapiens and Medtronic electrode (Figure 1). Finally, this model is used to select the stimulation settings of the Sapiens electrode.

Components

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Literature study

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Modeling of the micro-macro test electrode

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Develop a stimulation strategy for the Sapiens electrode based on the model results

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Thesis writing

Educational program

MSc BMT/EE

Research theme

From Neural Circuit Behaviour to Human Sensory-Motor Function

Principal Investigator track

Ciska Heida:

Central motor control

Supervision and info

Kees van Dijk

Ciska Heida