Radio Frequency Ablation is used to treat cancer and many other medical problems throughout the body. Ablation is a medical term that refers to any procedure performed to destroy diseased or damaged tissue in the body. Catheter ablation is a technique in which a thin tube, or catheter, is inserted through the skin or threaded through the blood vessels to the site of disease. Extreme heat or cold, alcohol, chemotherapy drugs or other therapies are delivered through the catheter to the diseased tissue.
RFA treats disease with heat, a technique preferred by many cancer experts because it can reliably destroy a small, targeted area of tissue without healthy affecting structures beyond the treatment site. With RFA, the doctor can pinpoint target areas with accuracy and monitor and control the temperature of heat therapy.
RFA and other catheter ablation procedures often are performed without surgery by interventional radiologists. These physicians specialize in the use of X-rays and other techniques such as ultrasound, computed tomography (CT) and magnetic resonance (MR) to see inside the body without surgery. Flexible thin tubes (catheters) are inserted through skin or blood vessels and guided to the treatment site.
Miniature instruments can be inserted through the tube to perform a variety of treatments that otherwise could only be performed with more invasive open surgical procedures. Catheter ablation also can be performed by surgeons as a surgical procedure called intra-operative catheter ablation. There are a number of differences between surgery and interventional radiology (IR). IR treatment tools are usually inserted through a small nick in the skin. There are no surgical incisions, no stitches and no scars. General anesthesia is not needed for many IR procedures, and in most cases they are less painful and have fewer risks and complications than surgery. Most conditions treated with IR can be done in an outpatient setting, or require hospitalization for only a brief time. Patients treated with IR can expect shorter hospital stays – and faster recoveries – than surgical patients. Many people resume normal activities within a few days after RFA or other IR procedures.
About RFA Procedures
The safety and effectiveness of RFA is well known and the technology has been approved by the Food and Drug Administration (FDA). Countless patients with a variety of medical problems have been treated with the technique. RFA has been used for many years to treat painful bone growths, destroy nerve fibers and relieve chronic pain, remove small growths from the skin and stop excessive bleeding during surgery. More recently, the technique has become a standard treatment for some heart rhythm disorders and inoperable liver tumors. Many ongoing studies are testing RFA as a therapy for various types of cancer and disease.
In RFA, energy is delivered through a metal tube (probe) inserted into tumors or other tissues. When the probe is in place, metal prongs open out to extend the reach of the therapy. RF energy causes atoms in the cells to vibrate and create friction. This generates heat (up to 100o C) and leads to the death of the cells.
RFA may be performed with general anesthesia, or with light sedation (medications to make the patient drowsy and relaxed). If general anesthesia is not used, a local anesthetic is given to numb the skin and underlying tissues. Most patients do not experience pain or serious side effects during or after the procedure.
About RF Energy
RF is a form of electromagnetic (EM) energy, which is formed from waves of electric and magnetic energy moving together (or radiating) through space at the speed of light. This type of energy is a constant presence in our natural environment – visible light, radio waves and microwaves, for example, are forms of EM energy.
Electromagnetic energy is “non-ionizing” – which means it is not strong enough to ionize atoms and molecules in cells (ions are electrically charged particles that, like magnets, are drawn toward positive or negative poles). “Ionizing” radiation (e.g. gamma rays and x-rays), on the other hand, affect the chemical makeup of cells, and alter their genetic code.
Radiofrequency energy is safer than many cancer therapies because it is absorbed by living tissues as simple heat. Regardless of the heat source, cells will die when they reach a certain temperature. But RF energy and the heat it generates do not alter the basic chemical structure of cells.
After RFA, computed tomography (CT) magnetic resonance (MR) or other images are taken to be certain that the treatment has been effective. If all diseased tissue has not been destroyed, RFA usually can be repeated. During the first week after treatment, the dead tumor will seem to have “grown” in size. Over time, the dead tissue shrinks or disappears altogether as it is gradually absorbed and excreted like other waste products in the body.
What are the Complications of RFA?
RFA has a very low complication rate. Studies of the technique report complications in only 1 percent to 4 percent of patients, depending on the type of disease treated and the overall health of the patient. Most complications are minor and go away on their own. Infection is rare in non-surgical RFA, because there is no open wound and the treatment site is not exposed to potential sources of infection. The procedure is seldom painful, and any discomfort can be controlled with medications. One advantage of RFA compared to surgery is the very low risk of serious blood loss (hemorrhage). The heat that kills diseased tissue also causes blood to coagulate. In fact, RFA sometimes is used by surgeons to control bleeding during operations.
What Conditions Can Be Treated with RFA?
RFA is a proven therapy for many conditions, including certain cancers, and many studies are ongoing to determine its potential to improve outcomes for patients with many types of cancer and other medical problems.
Source: Society of Interventional Radiology © 2003, www.SIRweb.org