I. Overview of neurointervention
As a new and rapidly developing clinical treatment method, interventional therapy has become one of the three major medical treatments (i.e., medical therapy, surgical therapy and interventional therapy, also known as the three major medical technologies in terms of medical technology). Interventional therapies can be simply divided into neurointerventional therapies, cardiac interventional therapies, and peripheral interventional therapies. Although neurointerventional therapies are relatively late in development, difficult to learn and master, and have high clinical treatment risks, they have been developing rapidly in recent years, and their clinical applications are becoming increasingly popular and their therapeutic effects are getting better.
From the perspective of the discipline, as a marginal discipline, neurointervention is usually called interventional neuroradiology or neurointerventional radiology, therapeutic neuroradiology, endovascular neurosurgery ( endovascular neurosurgery, or interventional neurosurgery;
It is usually described simply as the direct or adjunctive treatment of certain diseases of the central nervous system, usually under X-ray surveillance; usually neurointerventional diseases are vascular diseases, including cerebral infarction, transient ischemic attack (TIA), cerebral blood supply deficiency, cerebral venous sinus thrombosis and ischemic cerebrovascular diseases such as central retinal artery or vein thrombosis or embolism within the arteries or venous sinuses Embolization of intracranial aneurysms, cerebral arteriovenous malformations, dural arteriovenous fistulas, carotid cavernous sinus fistulas and spinal vascular malformations, as well as embolization and intra-arterial chemotherapy for craniofacial vascular malformations and tumors of the skull, brain, spinal cord and spine.
From the diseases treated by neurointerventional therapy, we can see that the above name of neurointerventional discipline is not comprehensive and accurate enough, and it seems to be more appropriate to call it interventional neurology. The basic features of neurointerventional treatment are minimal trauma, certain efficacy and wide indications.
Interventional treatment of ischemic cerebrovascular disease
According to the domestic flow survey data, the incidence of cerebrovascular disease in China is 109.7/100,000, the prevalence is 245.6/100,000, and the mortality rate is 77.2/100,000, of which ischemic cerebrovascular disease accounts for about 70~80%; according to the large number of cases reported in China, the disability rate of cerebral infarction is 84% (including 67% of moderate and severe disability), and the recurrence rate is 60%; TIA, according to The morbidity and mortality rates of cerebrovascular disease are higher in elderly people over 60 years of age, with 1325.7/100,000 and 886.1/100,000 respectively, and some authors believe that the peak age of cerebral thrombosis in China is around 65 years.
1. Endovascular dilation and stent placement for intracranial and extracranial artery stenosis: Intracranial and extracranial artery stenosis is one of the important morbidity and disease factors of cerebrovascular disease, and about 70% or more of patients with ischemic cerebrovascular disease have stenosis of intracranial and extracranial arteries. The stenosis of intracranial and extracranial arteries can directly lead to cerebral ischemia in one case, secondary thrombosis at the stenosis can cause cerebral ischemia in the other, and atheromatous plaque or attached thrombus at the stenosis can block the downstream cerebral vessels causing cerebral ischemia in the third case.
Because of the relatively high rate of endovascular dilation complications and restenosis in arterial stenosis, dilation with stent placement is now generally used. Stenting angioplasty for extracranial stenosis of the carotid and vertebral arteries has been reported in a large number of cases, with a success rate of 97% or more, complications of 4-11%, and restenosis (or recurrence) rates of 4-8%, and can be repeated. The main complication of this procedure is the dislodgment of atheromatous plaque or attached thrombus in the vessel wall during balloon dilatation of the stenotic vessel and stent placement.
In recent years, the use of cerebral protection devices for dilation and stenting of carotid artery stenosis has been reported overseas, and the complications of treatment are only 0-2%. In March 2002, Beijing Hospital introduced FilterWire (tentatively translated as “filter wire”, a cerebral protection device for intravascular dilatation and stent placement) and Andioguard (tentatively translated as “vascular umbrella”, also a cerebral protection device for intravascular dilatation and stent placement) with the approval of relevant state departments, and obtained the qualification certificate for using them after relevant training, and was the first in China to use cerebral protection devices for the dilatation and In June 2002, the cerebral protection device will be gradually used in China.
Although the initial results reported for endovascular dilation with stenting are better than those for carotid endarterectomy, convincing long-term follow-up results are lacking, and the final results of a randomized controlled study with carotid endarterectomy are not yet available. Endovascular dilatation and stenting of carotid and vertebral artery stenosis are currently emerging in China, and it is believed that, with regular implementation, they will help reduce the incidence and recurrence of these diseases, reduce disability and death, and improve the quality of life of patients.
Although the use of endovascular balloon dilation for intracranial artery stenosis dates back to 1980, stent placement in intracranial arteries was only introduced in 1996 on a trial basis due to the difficulty of delivering stents into the skull and intracranial arteries due to their tortuous course and the softness of stents, as well as the fear of occlusion of important branches of intracranial arteries. In February 2001, Beijing Hospital was the first hospital in China to use stent placement to treat atherosclerotic stenosis of intracranial arteries.
To date, about 200 cases of intracranial stenting have been officially reported worldwide. Therefore, intracranial stenting is still in the exploratory stage, and its clinical efficacy remains to be observed. For stent placement treatment of atherosclerotic intracranial artery stenosis, we currently perform it only in the following cases.
(1) Stenosis greater than 60%, especially in cases with poor collateral circulation;
(2) Cases with recurrent TIA or stroke in the responsible stenotic artery and where medical drug therapy is ineffective or has poor results;
(3) Patients or family members who fully understand the condition and choose stenting treatment. When stenting is performed, attention should be paid to the preoperative, intraoperative and postoperative medical drug coordination treatment, as well as the long-term follow-up of treatment results.
2.Intra-arterial thrombolysis for acute cerebral infarction: Although there are still many problems in the practical operation or feasibility of intra-arterial thrombolysis as a routine treatment in a large area, from the available reports, its effect in treating acute ischemic cerebrovascular disease is better than intra-venous thrombolysis, or at least has the same effect as intra-venous thrombolysis. From the actual operation of the arterial group (Beijing Hospital is the responsible unit of the arterial group) of the national “Ninth Five-Year Plan” research project “clinical control study on the treatment of acute cerebral infarction in early stage (within 6 hours)”, it can be seen that as long as there is strong leadership and standardized management, close cooperation of related departments, and skillful mastery of neurointerventional insertion, the treatment of acute ischemic cerebrovascular disease is better than intravenous thrombolysis. The actual operation of the arterial group (Beijing Hospital is the responsible unit of the arterial group) shows that as long as there is strong leadership and standardized management, close cooperation between relevant departments, proficiency in neurointerventional intubation techniques, and strict control of the time window of intra-arterial thrombolysis and the dosage of thrombolytic drugs, better treatment results can be achieved.
Interventional treatment of hemorrhagic cerebrovascular disease
1.Treatment of intracranial aneurysm by intravascular embolization: spontaneous subarachnoid hemorrhage (SAH) in the elderly is a common hemorrhagic cerebrovascular disease. The annual incidence of spontaneous SAH is 5~20/100,000, and the prevalence rate is 31/100,000 in a survey conducted in six provinces and cities in China, which is 4/100,000. The cause of spontaneous SAH is thought to be 60-70% of intracranial aneurysm rupture and bleeding, and the early mortality rate of the first rupture and bleeding is as high as 36-40%, and the mortality rate of subsequent re-bleeding is higher.
Therefore, for spontaneous SAH, it is generally unacceptable not to look for the cause of bleeding, and it is mostly believed that digital subtraction angiography (DSA) should be performed as early as possible; if an aneurysm is found, it is mostly advocated that it should be embolized as early as possible (if embolization is not suitable, it can be surgically clamped). In this way, the aim is to eliminate the risk of rebleeding as early as possible, and also to facilitate lumbar puncture or other means to drain the subarachnoid space and to deal with a series of clinical problems after SAH, such as possible vasospasm and hydrocephalus.
Guglielmi detachable coil (GDC) has been used to embolize intracranial aneurysms for 12 years in foreign countries and 5 years in China. It has become one of the main clinical treatment methods comparable to surgical clamping of aneurysms because of its reliable efficacy, minimal trauma and good treatment safety. In comparison, the treatment of aneurysm by intravascular embolization is more suitable for patients with poor general conditions and cannot tolerate surgery. The use of three-dimensional cerebral angiography machine in China in the past three years or so has made it possible to observe aneurysms from any angle in space, making aneurysm embolization treatment more thorough and safe.
At present, embolization of aneurysms with liquid embolic agents has started to enter the clinic in foreign countries; in China, the treatment of wide neck aneurysms with aneurysm neck remodeling technique and stent + GDC embolization is gradually carried out; new and improved spring coils are also being studied and used. It is believed that these will help the treatment of refractory types of aneurysms, reduce the cost of treatment, and further improve the efficacy. Recent preliminary reports from international randomized controlled clinical studies of aneurysm embolization and surgical treatment of large numbers of cases show that patients in the embolization case group have a higher quality of survival than the surgical group.
2, interventional therapy for other hemorrhagic cerebrovascular disease: carotid cavernous sinus fistula preferred by intravascular embolization treatment is effective, is a recognized fact; cerebral dural arteriovenous fistula surgery complex and difficult, embolization treatment has a unique efficacy and good results. Embolization of cerebral arteriovenous malformations is also one of its main treatment options. It is important to consider that if the patient does not start with hemorrhage, if the vascular malformation mass is large and difficult to embolize completely, and if there are no dangerous structures within it that cause hemorrhage (e.g., aneurysms, large high-flow arteriovenous fistulas, etc.), it is not necessary to get rid of the malformation mass completely, and continued observation is a treatment option as long as it is done to relieve symptoms (e.g., headache, epilepsy, etc.). In addition, interventional embolization plays an irreplaceable and important role in the treatment of all types of spinal cord vascular malformations.
Summary
Compared with medical drug treatment, interventional therapy can directly reach the lesion site for treatment, making the lesion clearly accessible and the treatment result clear and easy to determine; compared with surgery, interventional therapy is minimally invasive, enabling the treatment of many patients who could not tolerate surgery in the past due to advanced age and abnormalities of other organs or systems, and also enabling the treatment of some lesions that were inoperable or very dangerous in the past. Interventional therapy is a relatively young and highly promising clinical treatment method that requires the support of other related disciplines and perhaps a large number of medical personnel to dedicate their lives to it.