What Are Stimulation Electrodes?

Also known as brain pacemaker therapy, it implants electrodes into specific neural nucleus groups in the brain (such as the subthalamic nucleus) to release high-frequency electrical stimuli and inhibit the electrical impulses of these neurons that are over-excited due to the reduction of dopaminergic neurons , Reducing its state of excessive excitement, thereby reducing the symptoms of Parkinson's disease. Deep brain electrical stimulation is a stereotactic surgery in which a stimulating electrode is implanted into a lesion in the brain of a patient with Parkinson's disease, a stimulus generator is implanted under the skin of the patient's chest, and electrical pulse stimulation is applied to a specific part of the brain. So as to improve the symptoms of Parkinson's disease, primary tremor and other diseases. This operation can effectively reduce the main symptoms of Parkinson's disease such as tremor, rigidity, and bradykinesia.

EEG indications

Suitable for a wide range of intractable nociceptive pain and neuropathic pain. Nociceptive pain generally chooses to stimulate the periventricular gray (PVG) and posterior ductal gray (PAG) of the midbrain. Neuropathic pain often chooses to stimulate VPL or VPM.

EEG contraindications

With spinal cord electrical analgesia.

EEG anesthesia

Local anesthesia.

EEG Stimulation Posture

Generally supine position.

EEG surgery steps

1. The patient is fitted with a stereo headpiece, MR scan, and the target coordinates of the stimulation electrode implantation are calculated. The reference positioning coordinates of each target point are PVG: 2 to 8 mm in front of the PC, 0 to 8 mm above the AC-PC line, and 2 to 3 mm beside the AC-PC line; PAG: 3 mm in front of the PC to 2 mm behind the PC 3 mm above AC-PC line to 7 mm below AC-PC line, 2 to 3 mm next to AC-PC line; VPL: 3 to 4 mm in front of PC, 4 mm above AC-PC line, and AC-PC line to side 15 to 17 mm; VPM: 4 to 5 mm in front of the PC, 4 mm above the AC-PC line, and 8 to 10 mm beside the AC-PC line.

2. Fixed stereotactic head frame, straight forehead scalp incision, drill the skull, cut the dura, and implant electrodes into the predetermined target position.

3. Connect a stimulus generator for experimental electrical stimulation, adjust the position of the electrodes until the electrical stimulation can produce a satisfactory analgesic effect, and securely fix the electrodes.

4. The stimulus pulse generator is buried in the subcutaneous tissue behind the ear or under the collarbone, and the lead is firmly connected to the stimulation electrode through the subcutaneous tunnel.

5. Use a dedicated external stimulation program controller to adjust and determine the optimal stimulation parameters of the pulse generator for long-term electrical stimulation treatment. ^[1]

EEG precautions

1. VPL or VPM stimulation is generally selected on the opposite side of pain, PAG or PVG stimulation can be selected on the contralateral or bilateral side of the pain. To avoid surgery on the main cerebral hemisphere, you can also choose the same side of pain.

2. The fixation of the stimulating electrode must be firm and secure, to avoid the electrode position from causing changes in the stimulus position or damaging important structures in the deep brain. ^[1]