Introduction to Screening and Implant Techniques
Screening Test for Neurostimulation
Complete System Implantation
Preoperative Considerations and Care
Neurostimulation System Implant Procedure
Postoperative Care

Either a fully implanted battery system or a radio-frequency system can be implanted as deemed appropriate by the physician. The procedure is performed in two steps: The implantation of a lead (the lead placement may have already been done in the screening test), followed by the implantation of a neurostimulator.

Before implantation, the physician, with input from the patient, identifies the best placement site for the neurostimulator. The physician should use a skin marker to mark the site. The abdominal area (away from the beltline) is typically recommended as the placement site for the neurostimulator. (See Preoperative Considerations and Care for more information on determining the implant site.)

At the outset of the surgical procedure, the clinician should ensure that the appropriate settings have been programmed (i.e., 0 V amplitude, a pulse width of 210 µs, and a rate of 30 pps). Following implantation, the clinician adjusts the stimulation parameters as necessary to achieve effective pain relief, using the results of the screening test as a guide.

For more detailed information about the implant procedure, refer to the technical manual and the implantation guide available from Medtronic.

Prepare the patient using fluoroscopy to identify the appropriate vertebral intervals. Mark those intervals on the patient's skin.
Use a local anesthetic so the patient is alert and able to respond during the procedure. Then, insert a needle at the spinal location appropriate for the patient. Confirm the needle placement using fluoroscopy.
Introduce the lead through the needle and advance the lead tip to the spinal location corresponding with the patient's pain. Confirm lead placement in the epidural space using fluoroscopy. If more than one lead is to be used, repeat steps 2 and 3, placing a second needle for the second lead.
Connect the lead(s) to an external cable and the cable to an external source of power called a screener. Test the effect of stimulation and adjust the parameters for optimal pain relief. The patient will provide verbal feedback regarding where he or she feels paresthesia (tingling) over the pain area. If neccessary, adjust the lead position(s) for optimal pain relief. When good paresthesia is achieved, anchor the lead(s) in place. The patient uses the screener for several hours up to a few days to test the effectiveness of stimulation on his or her pain.
If the patient achieves pain control of >50% during the screening test period, the physician and patient may agree to proceed with the implantation of the system.
	If the physician uses a surgically-placed, paddle-type lead(s), proceed with step 6.
	If the physician uses the same lead(s) as used during the screening test, proceed to step 8 for the internalization of the neurostimulator.
	If the physician uses a percutaneously placed lead(s), but not the one(s) used during the screening test, repeat steps 1-4 to place the lead(s) for the implanted system, then continue with step 8 for the internalization of the neurostimulator. Repeat Steps 1-4; then go to Step 8.
Perform the appropriate surgical procedure to expose the dura mater. Introduce a lead blank (same size and shape as the lead, but without electrodes) at a shallow angle to prepare the pathway. Remove the lead blank. Pass the surgical lead until the entire lead paddle is in the epidural space.
When the lead is in place, connect the lead to an external cable, and the cable to the screener. Adjust the lead position for optimal pain coverage (as was done during the screening test, step 4). When testing is complete, disconnect the external cable.
Anchor the lead and proceed with the implantation of the neurostimulator. Create a subcutaneous pocket (generally in the patient's abdominal area) for the neurostimulator.
Create a tunnel for the extension. Pass the extension through the tunnel and connect to the lead. Next, connect the other end of the extension to the neurostimulator.
Use the programmer to communicate with the neurostimulator non-invasively, establish initial parameter settings, and verify system operation.
Close all incisions and use the programmer to optimize pain control.

Citations regarding Screening Test and Implant Techniques. . .

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Introduction to Screening and Implant Techniques
Screening Test for Neurostimulation
Complete System Implantation
Preoperative Considerations and Care
Neurostimulation System Implant Procedure
Postoperative Care