Halifax Health offers several techniques for patients with AVMs or aneurysms once considered impossible to treat because of their location or size.
Advanced Surgical Techniques
Carotid endarterectomy is a procedure used to remove atherosclerotic plaque from the carotid artery when this vessel is blocked. It has recently been proven that for certain patients with minor strokes or TIAs, carotid endarterectomy is highly beneficial in preventing future strokes. This procedure is also beneficial for some patients with blockage of the carotid arteries who have not had previous symptoms.
Stereotactic Microsurgery for AVMs and Aneurysms
Stereotactic microsurgery is one of the most dramatic new surgical procedures for AVMs and certain aneurysms that were once considered untreatable. It employs sophisticated computer technology and geometric principles to pinpoint the precise location of the AVM. During the procedure, a custom-fitted frame is attached to the patient’s head and three-dimensional reference points are established using CT or MRI. This technique allows neurosurgeons to locate the AVM within one or two millimeters so they can operate, using microscope-enhanced methods and delicate instruments, without affecting normal brain tissue.
Stereotactic Radiosurgery for AVMs
Stereotactic radiosurgery is a minimally invasive, relatively low-risk procedure, that uses the same basic techniques as stereotactic microsurgery to pinpoint the precise location of the AVM. Once located, the AVM can be obliterated by focusing a beam of radiation that causes it to clot and then disappear. Due to the precision of this technique, normal brain tissue usually is not affected. This procedure is generally performed on an outpatient basis.
Revascularization of the Blood Supply
Revascularization is a surgical technique for treating aneurysms or blocked cerebral arteries. The technique essentially provides a new route of blood to the brain by grafting another vessel to a cerebral artery or providing a new source of blood flow to the brain.
Interventional Neuro-radiology Techniques
In addition to new techniques, Halifax Health is pioneering a number of new interventional radiology procedures to prevent stroke in patients with selected high-risk AVMs, aneurysms, and partially blocked arteries. These endovascular procedures are performed within the blood vessel.
Endovascular Treatment of Aneurysms
Endovascular treatment of aneurysms is a new interventional neuro-radiologic technique, which greatly benefits patients with serious medical conditions who are unable to sustain the stress of surgery. Platinum coils are guided into the aneurysm via a catheter, creating a clot that effectively closes the aneurysm off from the surrounding circulation, preventing the risk of hemorrhagic stroke in the future.
Endovascular Blood Clot Removal
The Solitaire and Penumbra™ devices are designed to restore blood flow in large vessel ischemic strokes though a minimally invasive procedure. Once the location of the clot has been identified using angiography, the thrombectomy device is inserted through a small incision in the femoral artery in the groin. Under x-ray guidance, the thrombectomy device is maneuvered up to the carotid artery in the neck, a guidewire and the thrombectomy devices are deployed just beyond the clot. The physician then deploys the thrombectomy device to engage and ensnare the clot. Once the clot is captured, the device is completely removed from the body.
Endovascular Treatment of AVMs
Endovascular treatment of AVMs is also available at Halifax Health. One innovative form of treatment involves use of a “super glue” substance introduced via a tiny catheter to reduce the size of the AVM and facilitate further microsurgical or radiation treatment. In some cases, it is possible to completely block off and cure the AVM with endovascular treatment alone.
Angioplasty and Stenting of Vessels in the Neck and Brain
Angioplasty and stenting of vessels in the neck and brain are other new endovascular procedures. Cerebral angioplasty is similar to a widely used cardiology procedure, and is used to open partially blocked vertebral and carotid arteries in the neck, as well as blood vessels within the brain. Stenting of carotid or vertebral arteries and large cerebral veins involves use of a fine, tubular wire mesh to hold the vessel open.
The clot-dissolving drug tissue plasminogen activator (tPA) to treat strokes caused by blood clots. (Blood clots cause about 80 percent of all strokes.) tPA dissolves the clot and restores blood flow to the brain. tPA carries a risk of bleeding in the brain, but its benefits outweigh the risks when an experienced doctor uses it properly. Not every stroke patient, particularly those having a hemorrhagic stroke, should be treated with tPA. That’s why it’s extremely important to determine the type of stroke very quickly. tPA is effective only if given promptly. For maximum benefit, the therapy must be started within three hours of the onset of stroke symptoms. That’s why it’s so critical that medical professionals and the public recognize stroke as a medical emergency and respond immediately.