Interventional Radiology Offers Surgery Alternative To Many
By Charlotte Bell, M.D.
Keith J. Ruskin, M.D.
Interventional radiologists differ from conventional surgeons by using digital technology to make repairs in the body and by making tiny or no incisions. The radiologist does not need to look directly at the area in which he is working. Instead, he inserts a tiny endoscope (a tube with flexible glass that allows the viewer to see inside the body) through a catheter placed in the patient's vein or artery. These flexible endoscopes use state of the art lenses to transmit images to a monitor (screen) placed near the patient. The radiologist watches the monitor and manipulates his instruments outside the body.
Many procedures can be done in one day and can be performed with the patient sedated but conscious.
Interventional radiology has five main benefits:
How is interventional radiology performed?
At the initial visit, the radiologist reviews the patient's medical records, and discusses the procedure, its risks and its benefits. Patients usually can be admitted on the same day. Most of the procedures described in this article begin with an intravenous catheter placed in the hand or arm that delivers medication to help the patient relax, and to minimize any discomfort. Patients are conscious, and can talk with their health-care team.
In most cases, a specially trained nurse monitors vital signs such as heartbeat and blood pressure throughout the procedure. For children and patients with serious medical problems, an anesthesiologist will be on hand to provide anesthesia, if necessary.
Once the patient is comfortable, the radiologist paints an antibacterial solution on the skin where the catheter will be placed. This decreases the possibility of infection. Sterile surgical drapes are placed around the area to prevent any contamination with germs.
The radiologist then injects the skin with a small amount of local anesthesia such as lidocaine. This rarely causes any significant discomfort. When the skin is numb, a hollow needle or plastic sheath is placed directly into a large blood vessel. Catheters can then be passed through the sheath or needle.
"The patient had already been through two operations to remove gallstones from the channel (duct) between the gall bladder and intestine through which bile drains. Nevertheless, classic x-ray images continued to show something the size and shape of a gallstone still present in the duct, causing a build up of bile and pain.
"However," adds Dr. Pollak "catheters placed in the duct showed no evidence of a stone. We were able to pass a tiny endoscope directly into the duct and were surprised to see a tiny polyp obstructing bile flow. Previous attempts at catheter placement flattened the polyp against the wall of the channel so it seemed to disappear. We were able to definitively find the problem and remove the polyp without the patient undergoing further surgery."
What health problems can be diagnosed and /or treated by interventional radiology?
Some of the most common interventional radiology procedures are angioplasty, stent grafting, embolization, tumor embolization, fibroid embolization and vertebralplasty.
Descriptions of Interventional Radiology Procedures
Angioplasty: Opening narrowed arteries
Blood flow can also be restored to arteries that have been completely obstructed by clots by placing chemicals to dissolve the clots in specific locations or by mechanically removing clots from larger vessels.
In some cases the radiologist will also place a stent- a small mesh cylinder- in the artery using the same technique as in the angioplasty, to help keep the artery open after angioplasty.
Most patients with abdominal aortic aneurysms are elderly and have additional serious diseases that may prevent them from undergoing surgery. The stent graft procedure offers a highly successful alternative to surgery and minimizes the risk of aneurysm rupture.
Embolization: Plugging blood vessels
Uterine fibroid embolization
"Patients usually have some discomfort for 7-10 days after the embolization while the tumor is shrinking, although less than the pain anticipated from a surgical incision. Most patients can return to work a week after embolization, compared to a 4-6 week recovery from surgery," says Dr. Melvin Rosenblatt, associate professor of radiology and co-director of the Center for Interventional Radiology at Yale University School of Medicine.
Not all centers offer fibroid embolization and not all women are candidates for the procedure. Approximately 1-2% of women will have complications from the procedure including infection and premature menopause.
Blood Clots and Varicose Veins
Another technique, radio frequency ablation, uses energy waves to reduce or eliminate varicose veins. Although varicose veins are not a life-threatening problem, many patients find that they significantly interfere with their activity level and daily functioning.
"If treated in the first few weeks after onset of symptoms, vertebralplasty can greatly decrease pain for over 80% of osteoporosis patients," said Dr. Michele Johnson, associate professor of radiology at Yale University School of Medicine and director of Interventional Neuroradiology. "Patients usually report less pain and improved mobility within 24 hours," she adds.
Help for Cancer Patients
A radiologist can insert a small catheter into the chest cavity that can be left in place, allowing the fluid to drain. Chemicals can then be inserted through the catheter to minimize or prevent the fluid from building up again. With the catheter, patients no longer need to undergo a painful daily procedure at the hospital to have the fluid drained.
What the future holds