"Interventional neuroradiology," or the process of using 3-dimensional images to plan and perform noninvasive surgery to "intervene" and treat head, neck and spine vessel conditions, represents a major medical breakthrough that is saving lives.
What is Interventional Neuroradiology?
Originally developed in the 1980s, Interventional Neuroradiology is an exciting new medical specialty that originated when neurosurgeons and radiologists began working together to develop alternative, less invasive methods of treating head, neck and spine conditions for patients in whom traditional surgery wasn't an option. Significant advances in medical "imaging" technology that allows doctors to view real time artery and vessel anatomy and to track the flow of blood through the body to help identify blockages, malformations and tumor or lesion development without undergoing surgery, is the backbone of this specialty.
Equally significant is the recent development of revolutionary new micro tools to help doctors provide treatment to very specific target locations including some that are unreachable through traditional surgery. Most interventional neuroradiologic treatments are delivered through a very tiny catheter or tube inserted using local anesthetic into an artery in your groin. The catheter is then slowly fed through your vessels until it reaches the treatment location. Similar in concept to GPS in a car, using 3 dimensional images of your vessels, doctors create a "roadmap" in advance of the procedure to establish the path they want the catheter to take as they direct it to the treatment location. During the procedure, real time images of your vessels are displayed on a monitor so that your doctor can properly guide the catheter. Think of it as constructing a protective tunnel that allows doctors to insert medication or microscopic treatment devices on one side and deliver them on the other side to the precise treatment location!
Interventional neuroradiology offers promising new non-invasive surgical treatment to many patients who previously would have had to undergo open, traditional surgery. Hospitalization for most interventional neuroradiological procedures is 1-2 days.
Interventional Neuroradiology Treatment Methods
The foundation of interventional neuroradiology treatment is the ability of doctors to obtain detailed images of the head, neck or spine that show the path of blood flow in those areas and allow doctors to create a detailed 3 dimensional image of artery and vessel anatomy. Using this imagery, doctors are able to spot and diagnose blockages, malformations and to study the vessels that circulate to (and feed) tumors or lesions.
The most advanced interventional medical imaging technology in the world is biplane imaging, a digital x-ray technology that uses two mounted rotating cameras, one on each side of the patient, to take simultaneous pictures of the target area front to back and side to side. It produces an image quality that is capable of showing detailed vessel and soft tissue anatomy, and together, the two images are used to create a 3 dimensional portrait of the affected area, lowing doctors to spot and more accurately pinpoint, diagnose and treat head, neck and spinal conditions.
Biplane imaging also allows doctors to follow the path of blood flow through your vessels and to create a "roadmap" for reaching and treating the precise location of disease or malformation. Also known as angiography, this process involves inserting a small catheter into an artery, a similar procedure to getting an IV. A small amount of dye that makes it easier to see the blood flow through your vessels is injected into the catheter. The biplane imaging cameras take detailed x-rays that are shown in real time on a monitor just a few feet from where your doctors watch it travel through your system. They are quickly able to determine if there are blockages or malformations such as aneurysms and they are able to obtain a map of your vessels in order to determine the best route or means of reaching the target area to provide treatment. They are also able to determine a lot about your condition that will establish what treatment they should provide. Some conditions are unable to be treated through interventional methods and may require traditional surgery.
Using the roadmap of your vessel anatomy and by overlaying images of the path your blood takes through those same vessels, doctors carefully plan and administer treatment. Delivered through a catheter or protective tube that is inserted in your groin using local anesthetic and then fed along the vessel roadmap to the treatment location, doctors use the catheter to deliver one of several different interventional treatment options. During the entire process, they are guided by the biplane imagery that is displayed in real time on a monitor just a few feet from where you are resting.
In order to cut off dangerous blood flow to an aneurysm, doctors use tiny, flexible coils to fill or "pack" the aneurysm, so that blood travels past and not through it. The coils are made of platinum so that they are visible by x-ray and are flexible enough to conform to the shape of the aneurysm. An aneurysm is a serious medical condition in which a thinning or weakening of a vessel may lead to swelling or bulging of the vessel wall, perhaps putting pressure on the brain. If left untreated, an aneurysm may rupture causing serious medical disability or death.
Using local anesthetic, a catheter is inserted into the femoral artery in your groin and using the vessel roadmap created by your physician, it is directed through your vessels into the opening of the aneurysm. One by one, coils are attached to a small delivery wire that your doctor threads through the catheter into the opening or "neck" of the aneurysm. Your doctor watches real time images of your vessels on the biplane imaging monitor and uses it to guide placement of each coil. Once the coil is in place, a small electrical current that you will not feel is sent through the wire to the coil and it detaches in the aneurysm. The aneurysm is packed with coils and in time, a membrane may develop over the neck of the aneurysm completely cutting off dangerous blood flow.
While coiling is a highly effective treatment method in many cases, aneurysms with a large opening or neck or those that are large in size, may not be good candidates for coiling treatment. In some cases coils will be used and a mesh tube or "stent" will also be placed over the neck of the aneurysm to prevent the coils from dislodging.
A stent is a small, mesh tube that is used to keep arteries open and free from blockage. As arteries harden, this can cause a narrowing or blockage of blood vessels that may restrict blood flow to the brain and lead to a stroke.
Using local anesthetic, a catheter is inserted into the femoral artery in your groin and using the vessel roadmap created by your physician, it is directed through your vessels to the area of the blockage. A balloon catheter is then used to inflate the artery wall, pressing the plaque against it and opening the artery. The stent is fed through the catheter as doctors watch images of your vessels on the biplane monitor and guide the stent into place so that it covers the plaque and will help keep vessels open.
This treatment method can be used alone or in conjunction with traditional surgery to reduce blood flow to certain vessels. Some common uses for embolization include blocking the blood supply to large tumors or other malformation (especially before surgery) and blocking the blood supply to enlarged cerebral arteries in order to prevent rupture.
Using local anesthetic, a catheter is inserted into the femoral artery in your groin and your doctor will use the biplane imaging system to direct the catheter through vessels to the location of vessels that are supplying blood to affected area or malformation Your doctor will then inject materials such as medical glue and particles intended to block blood supply.
Blood clots can be life threatening if they travel to the brain or other vital organ and obstruct blood flow and delivery of oxygen to the brain. If deprived of oxygen for even a short period of time, brain cells start to die and the part of the body that section of the brain controls is adversely affected. Blood clots are the leading cause of stroke.
Intra-arterial thrombolysis is a treatment method that allows doctors within 6 hours of a stroke, to deliver clot busting drugs (tissue plasminogen activator also known as TPA) directly to the site of the blood clot. Using local anesthetic, a catheter is inserted into the femoral artery in your groin and doctors use the biplane imaging system to identify the exact location of the clot, mapping the best path for guiding the catheter to it. Once the catheter is in place and using the imaging monitor to guide them, doctors inject the drugs directly into the clot breaking it apart into very small sections that do not pose a risk of blockage.
Vertebroplasty is a treatment administered by interventional neuroradiologists to stabilize broken bones in the spine. Often used to treat compression fractures precipitated by osteoporosis, a needle is inserted through the skin into the vertebra, where surgical bone cement called poly-methylmethacrylate is injected into the bone. More than one vertebra can be treated in a single procedure. Guided by x-ray imaging, doctors guide the needle to the exact location of the bone requiring treatment and once treatment is administered, most patients experience immediate pain relief.
Vasospasm is the narrowing of the vessels that supply blood to the brain. This condition can occur as the result of an aneurysm that has ruptured or bled and can lead to a stroke if enough blood does not reach the brain.
Using local anesthetic, a catheter is inserted into the femoral artery in your groin and your doctor will use the biplane imaging system to direct the catheter through vessels to the artery that is narrowing. Through the catheter, your doctor will inject medication to dilate the arteries.