Endovascular Neurosurgery is a minimally invasive approach for the treatment of Neurovascular diseases (Stroke). Conditions in the past that would have required surgical intervention such as aneurysms, vascular malformations, and tumors of the brain, spine, head and neck can be considered for treatment by using an endovascular approach to reach the lesion.
Rupture of an intracranial aneurysm can result in serious permanent neurological deficit or death. It is estimated that approximately 2% of the general population harbors a cerebral aneurysm. Of patients with hemorrhage, in spite of aggressive treatment 45-50% of patients die immediately or within two weeks. If untreated, up to half of the survivors will suffer significant neurologic injury or death from subsequent hemorrhage or vasospasm. Conventional treatment of an intracranial aneurysm has been by open craniotomy and clipping of the neck with various types of clips. Certain aneurysms bear unfavorable configuration, size of neck, or location, and therefore proper clipping may not be possible. With the introduction of transarterial intracranial navigation of catheters in the 1970's, a new era of possible endovascular occlusion of these difficult aneurysms began.
A new method of endovascular obliteration of intracranial aneurysms using Guglieimi Detachable colis (GDC) was developed atUCLAMedicalCenterin 1990. The aneurysm is reached using techniques for cerebral angiography. A small catheter is threaded from the femoral artery up into the major cranial vessel involved. A smaller microcatheter is then advanced into the aneurysm. The soft platinum GDC coils are then threaded through the catheter into the aneurysm. As the coil is advanced into the aneurysm it conforms to the shape of the aneurysm. By applying a low voltage direct current to a stainless steel wire at the base of the coil, the platinum coil is detached.
The platinum coils are extremely soft and have a preformed shape. Once extruded from the catheter tip, the coil forms a loop to prevent unnecessary stress to the aneurysm wall. The coils are available in a variety of lengths from 1- 30 cm. Each coil has its own preformed radius. One great benefit of these coils is the ability to withdraw the coil prior to final placement. This allows repositioning or possible exchange of the coil for a different size if it does not conform perfectly to the aneurysm. By packing the aneurysm with a number of coils, the aneurysm can be completely excluded from the circulation.
Cerebral AVMs are most commonly discovered in young adults. These lesions are usually detected in patients as the result of a seizure or hemorrhage. AVMs hemorrhage at a rate of 4% per year. Approximately half of these hemorrhages will carry significant morbidity or mortality, therefore when one considers management of a young patient with a brain AVM, the lifetime risk of hemorrhage can be substantial.
Treatment of brain AVMs has been greatly enhanced by adopting a team approach utilizing combined modality therapy. Using this strategy, a treatment plan is devised to offer the lowest risk yet highest chance of obliterating the lesion. The three modalities of treatment currently available include endovascular introduction of agents which occlude parts or all of the AVM, standard microneurosurgical techniques to remove an AVM or radiosurgery. Currently available endovascular techniques involve passing tiny catheters into the cerebral vessels feeding the AVM. Once the catheter reaches the nidus of the AVM, a glue material can be injected to occlude portions, or in some cases all, of the arteriovenous malformation. The endovascular technique carries a risk of 3-5% of serious complication, however it can make subsequent surgical removal of an AVM significantly safer, or can reduce the size of an AVM to a volume where radiosurgery carries a higher efficacy.
Figure 1 shows a brain AVM prior to and after ONYX (New embolic material) embolization of a portion of the AVM in the occipital portion. If the AVM is reduced in size significantly, the lesion may then be amenable to techniques of stereotactic radiosurgery where a focused beam of radiation is used at a one-time treatment. This radiation causes changes in the blood vessel walls, and over the course of 2-3 years the
A new Endovascular neurosurgery suite in the operating room that offers integrated neurosurgical and radiological capabilities. This state-of-the-art facility will help Endovascular Neurosurgery from the full spectrum of conventional Neurosurgery to more widely used minimally invasive methods, known as Endovascular neurosurgery.
Jikei University Center for Endovascular Neurosurgery treats patients with a variety of neurovascular problems that include narrowing of arteries that lead to strokes and brain aneurysms.
The new suite, which has a separate control room for X-ray and other imaging capabilities, will allow surgical staff to perform a wide array of procedures.
When stroke patients arrive at Emergency room, those patients can be immediately transfered to the Endovascular OR without time delay. Then patients will be performed diagnostic angiography followed by endovascular interventional procedures or conventional neuro-surgical intervention.