Neurointerventional radiologists are a critical part of the stroke team in hospitals and are actively involved in creating more stroke teams across the country. Stroke teams generally consist of emergency room physicians, neurologists, and interventional radiologists and/or neurointerventional radiologists.
As vascular experts, neurointerventional radiologists treat atherosclerosis, "hardening of the arteries," throughout the body. In patients at high risk of having a stroke, the narrowed section of artery may be reopened by an interventional radiologist through angioplasty and reinforced with a stent, thereby preventing the stroke from occurring.
Vascular stents are typically made of woven, laser-cut or welded metal that permits the device to be compressed onto a catheter and delivered directly into the hardened artery. In addition to diagnosing and treating those at risk for stroke, interventional radiologists use their expertise in imaging, angioplasty and stenting to treat those having an acute stroke.
For those having a stroke, it must first be determined which kind of a stroke the patient is having so the proper treatment can be given. The interventional radiologist interprets the non-contrast CT (computed tomography) imaging to determine if acute stroke patients are candidates for clot-busting drugs. CT is quick, inexpensive, and readily available.
If the stroke is determined to be ischemic (due to a blood clot), the interventional radiologist will assess what caused the clot, such as a clogged carotid or other artery, and can correct the underlying problem to prevent future strokes from occurring.
Treatment To Dissolve Blood Clots
If the stroke is due to a blood clot, a clot-busting drug, tPA (tissue plasminogen activator) can be given intravenously to break up or reduce the size of blood clots to the brain. This technique must be performed within three hours from the onset of symptoms.
When therapy cannot be initiated within three hours or when treatment with tPA during the first three hours is not sufficient to dissolve the blood clot, interventional radiologists (IR) that specialize in neurological procedures can provide intra-arterial thrombolysis treatment.
Using x-ray guidance, an interventional radiologist will insert a catheter through a nick in the skin at the groin and advance it through the femoral artery in the leg all they way to the tiny arteries in the brain where they place the clot-busting drug directly on the clot or to break up the clot mechanically.
When given locally this way, the tPA can be administered up to six hours after the onset of stroke symptoms. In many cases, the ambulance drivers will take a stroke victim past the three-hour window directly to the interventional radiology suite for assessment for this direct thrombolytic therapy. Often a significantly disabled stroke patient who receives this treatment can return to normal life with minimal or no after effects from the stroke.
The interventional radiologist will also assess what caused the clot, such as a clogged carotid or other artery, and can correct the underlying problem to prevent future strokes from occurring. Unfortunately, many hospitals in this country do not have stroke teams that can rapidly assess patients and provide treatment within the three-hour window. Interventional radiologists are actively involved in creating more stroke teams across the country. Stroke teams generally consist of emergency room physicians, neurologists and interventional radiologists.
Treatment for Hemorrhagic Stroke
NeuroInterventional radiologists can also treat ruptured aneurysms inside the brain causing hemorrhage into the subarachnoid space, which can cause stroke or death. During the embolization technique, an interventional neuroradiologists inserts a catheter through a nick in the skin of the groin and advances it to the site of the ruptured blood vessel. An embolizing agent (a substance that clots or closes off the bleeding blood vessel) is injected under X-ray guidance. Most commonly, tiny metal coils are used to embolize and block the abnormal blood vessel or aneurysm. The catheter is withdrawn and the coils remain to provide the occlusion. The same technique can be used to treat aneurysms and AVMs before they rupture. Surgery had been the primary treatment available until the platinum coil device was approved by the FDA in 1995.
