Chart illustrates the flow of current during the RFA procedure. (Provided by Valleylab)
The Equipment• Generator and grounding pads
Your body will be made into an electrical circuit-that's what helps produce the energy that heats and kills the tumor. A generator that the needle electrode is attached to will produce the energy that causes the heat, while grounding pads on your body will complete the circuit, allowing the needle electrode to destroy the tumor.
Your doctor will use imaging technology, such as ultrasound or a CT scan, to guide a needle electrode to the tumor. Ultrasound produces no radiation, although CT does.
• Needle electrode
Most RFA treatments use a 14 to 17.5-gauge needle. The needle is an electrode composed of an insulted shaft and a “live” tip, through which the energy will flow. Some RFA needles also have umbrella-like prongs that will extend from the tip and penetrate more of the tumor. Some needles are also water-cooled around the shaft, which allows for more even heating at the tip and reduces the risk of unwanted charring of tissue outside of the tumor.
You may be given a local or general sedative before the procedure. Your doctor will locate the cancerous cells with ultrasound, CT, or MRI, and guide the needle electrode into the tumor. The grounding pads will be attached to an area on your body near the needle electrode insertion site. The doctor will activate the generator, causing the needle electrode tip to begin emitting radio waves. The destruction process will probably take between 10 and 60 minutes. Your doctor may then relocate the needle electrode to heat another tumor or another area of the same tumor and repeat the process.
The needle electrode will be withdrawn, and the insertion site will be bandaged. Your doctor will not remove the tumor-the dead tissue will shrink and will gradually be replaced by scar tissue. Your doctor will monitor the tumor site with imaging technology to see if the tumor returns. If it does, RFA can be performed again without any major risks.