Radiofrequency Ablation of a Nerve
What is Radio-frequency Ablation and how will the procedure be performed? RFA is a technique used to destroy a nerve through the use of heat. This process can also be called radio-frequency rhizotomy. RFA is frequently used for back pain generated by the medial branch nerves of the facet joints.
You will arrive at the George Isaac Center approximately 45 minutes before your scheduled procedure. The nurses will complete the necessary medical forms, take your vital signs and start an IV. The IV will be used during the procedure to give you medication to help you relax and help with your discomfort. It is necessary that you remain awake during the procedure so that you can tell the physician if you have any unusual symptoms or discomfort. You will be transported by cart to a special room and positioned on a special table.
A grounding pad (dispersive electrode) will be applied to your skin. Patients frequently relate that the pad feels cold and sticky. The skin where the RFA is to be done will then be cleaned with antiseptic cleanser and then draped with sterile towels. Under fluoroscopy, a special X-ray machine, the doctor will determine the exact location(s) where the RFA will occur. The area(s) where the RFA needle/probe will be inserted is injected with local anesthetic (numbing medication similar to what your dentist uses). RFA is accomplished by positioning the insulated radio-frequency needle/probe under fluoroscopy (x-ray) to the location of the nerve that is to be burned. A sensory test is performed by stimulating the probes at 50 Hz (50 impulses per second). This is done to make certain that the patient does not feel stimulation anywhere other than the intended location. Most patients will describe this stimulating as a tingling or pressure sensation. A motor test is then performed by stimulating the probes at 2 Hz (2 impulses per second). This test is done to make certain that the probe will not heat any adjacent nerves. Most patients feel a thumping sensation with a twitching. If there is inappropriate muscle twitching the needle may need to be repositioned. An example of this is when RFA is being used for denervation of the medial branch nerve in the low back and the muscle twitching goes all the way down the leg. Once it is determined that the probe is positioned, exactly where it needs to be, the physician may inject numbing medication into the needle/probe to make the burning process less painful. The actual RFA will now occur, lasting anywhere from 1 to 5 minutes, depending on whether the process needs to be done more than once and the physician’s plan of treatment.
The burning of the nerve is not the result of the radio-frequency probe heating up, but is the result of the electric field lines emanating from the RFA probe tip. This electric field causes the ions in the tissue around the probe tip to move. This motion causes friction, which results in the tissue heating. The temperature of the tissue surrounding the probe is continuously monitored and maintained during RFA. Once the RFA procedure is complete, your skin will be cleansed and a band-aid dressings applied. You may remove the band-aids the following day. You will then be transferred by cart back to the recovery area where you will be monitored closely for the next 45-60 minutes. You will be given specific written discharge instructions and allowed to leave by wheelchair with your ride once the physician authorized your discharge.
What are the complications of these procedures? There is a remote risk of bleeding, infection, nerve injury, or allergic reaction to the medications used. Short term side effects may occur. These can be the spread of local anesthetic to nearby nerves, which may result in weakness or numbness that can last for several hours. After the RFA, you can expect one to two weeks of increased discomfort from the effect of the burning of the nerve.
What should I do after the procedure? Follow the discharge instruction sheet given to you prior to leaving the recovery area. This sheet provides you with detailed information regarding complications, side effects, restrictions and when to contact the Pain Medicine Center, or seek immediate treatment at the Emergency Room. A follow up appointment will also be scheduled for you prior to discharge from the Recovery Room.
Please remember that there are NO GUARANTEES that this procedure, or any other type of treatment, will relieve your pain.