interventional vascular embolization

Interventional vascular embolization, also known as superselective intra-arterial embolization, is one of the techniques of interventional endovascular therapy. This technology is a new diagnostic treatment technology developed on the basis of catheter technology in the 1950s. With the development of X-ray imaging technology, especially in the 1970s, computer digital subtraction imaging technology appeared. Doctors can put special catheters into the small arteries of almost any lesion area under the fluorescent screen, thus making the blood vessels in the contrast area more visible. Clear, relatively small wounds, more therapeutic purposes, more effective, and can be reused, leaving no serious soft and hard tissue deformities, has broad prospects for development. Treatment of diseases: peripheral arterial embolism Indication Because interventional vascular embolization has a prominent feature that is completely performed in the blood vessels, the surgery is highly targeted. The purpose of surgery is divided into three types: bleeding control, preoperative auxiliary embolization and therapeutic embolization. According to the methods used in the treatment and embolization materials, surgical indications can also be divided into three types, namely, some uncontrollable acute bleeding, diseases that are difficult to control bleeding, and good and malignant lesions that are not suitable for resection. 1. Various uncontrolled hemorrhagic hemorrhages, such as gingival bleeding in the central hemangioma of the jaw, major bleeding in the late stage of malignant tumor, and nosebleed. 2, high blood flow vascular malformations, such as vascular hemangioma derived from the external carotid artery, congenital or traumatic arteriovenous fistula. 3. Benign tumors rich in blood supply, such as giant hemangioma, neurofibromatosis, carotid body tumor, nasopharyngeal angiofibroma, jugular spheroid tumor. 4, malignant tumors wrap or erode important blood vessels, embolization plus drug treatment can control and slow the growth rate of tumors, prevent bleeding. Contraindications 1. Cardiovascular diseases such as vascular sclerosis hypertension, stage II diabetes, and blood system diseases. 2. Patients who are allergic to contrast agents. 3, elderly patients with weak or dyscrasia. 4. Patients who have previously had external carotid artery ligation should be carefully selected. Preoperative preparation 1. Regular skin preparation in the perineum and groin area. 2. Intravenous iodine allergy test. 3, banned diet before surgery. 4, 30 minutes before the operation, intramuscular injection of diazepam 10mg, atropine 0.5mg. 5, indwelling catheterization. Surgical procedure 1, femoral artery puncture and placement of contrast catheter Local anesthesia in the inguinal region was performed with 1% procaine or lidocaine, and the anesthetic was injected into both sides of the femoral artery to fix the blood vessels and prevent sputum. Use a sharp knife or a triangular needle to pick up the skin on the surface of the femoral artery, and perform a femoral artery puncture through the incision. Immediately after the puncture, the short metal wire is inserted through the puncture needle, the puncture needle is withdrawn, and the part is pressed to prevent bleeding. A trocar guide wire with a tee and communicating with pressurized saline is inserted into the femoral artery. The tee was opened and placed in a 4F contrast catheter. The catheter was placed under the monitor of the TV screen through the radial artery, abdominal aorta, and thoracic aorta to the aortic arch. 2, the common carotid artery and vertebral artery angiography Before the embolization treatment, the common common carotid artery and vertebral artery angiography should be performed to understand the traffic condition of the cerebral artery basement ring before and after, and to estimate the possible danger when the affected side is forced to embolize the internal carotid artery or common carotid artery. And its extent. At the same time as the internal carotid artery or common carotid artery angiography, the blood supply to the common carotid artery of the affected side should be compressed. 3, ipsilateral carotid artery angiography The purpose of the internal carotid artery angiography is to understand the relationship between the internal carotid artery (intracranial) branch and the blood supply to the tumor, to observe the abnormal anastomosis between the internal and external carotid arteries, and to perform common carotid angiography if necessary. 4. The external carotid artery and its branch angiography First, external carotid artery angiography is performed to understand the overview of hemangioma, the main blood supply vascular condition, blood flow velocity, and traffic conditions (including intracranial and extracranial traffic, and arterial and venous traffic). If the tumor is supplied by multiple branches of the external carotid artery, the blood flow rate is very fast, and abnormal traffic such as intracranial or external abnormal traffic or abnormal movements of the artery and vein is suspected, and then superselective contrast imaging of the external carotid artery branch is performed separately. In order to accurately predict the embolization effect, a cannula balloon can be placed in the external part of the external carotid artery or its branch to perform angiography to observe the developmental changes of the aneurysm. If the blood flow velocity is significantly slowed down, and the arterial phase and the venous phase are clearly staged, the embolization effect is good. If the development speed is still very fast, the arterial phase and the venous phase are not obvious, indicating that the vascular blood supply of the hemangioma is rich, and embolization is difficult. In this state of angiography, it is easier to find the mouth and mouth of the artery. If the external carotid artery ligation has been performed in the past, attention should also be paid to the branch of the blood vessel from the contralateral external carotid artery or from the ipsilateral vertebral artery. 5, external carotid artery and its branch embolization 1 embolic material: embolic material is divided into solid, liquid and micro-balloons. A. Solid materials: There are many types of solid materials, which are divided into temporary and permanent categories. Temporary embolization materials mainly include gelatin sponge powder and degradable suture. They are generally used for preoperative auxiliary embolization. They must be used in combination with tumor resection. The timing of surgery is best performed within 3 to 5 days after embolization to prevent embolization. The agent is degraded and absorbed, and the angiogenesis in the tumor area is recanalized. The permanent embolic material has 3-0 to 5-0 silk thread segments, freeze-dried dura mater, muscle fragments, steel rings, metal ruthenium, silicon-containing microspheres, and polyvinyl alcohol. Less successful recanalization after embolization, but also embolism and lateral flow phenomenon, and there are certain difficulties in the injection of solid materials, often resulting in tube blockage. B, liquid materials: liquid materials are anhydrous ethanol, 14-alkyl sodium sulfate, estrogen, hypertonic glucose, fish sodium glycerate, etc., which are mainly vascular sclerosing agents, can destroy vascular endothelial cells, form a wall thrombus, However, in the treatment of vascular malformations or tumors with very fast blood flow, the injection of liquid materials is prone to superfluous misplugging, embolic agents enter the pulmonary circulation; in slower bloodstream tumors, or in the late stage of embolic agent injection, injection pressure and speed Improper grasp, and prone to reflux sham plug, embolic agent into the internal carotid artery. C, micro-balloon: micro-balloon is divided into detachable and non-detachable two kinds, non-detachable balloon is mainly used to check and prevent embolic agent reflux, detachable balloon is mainly used for large movement, Venous fistula and preoperative adjuvant embolization. 2 embolization method: embolization method can be divided into direct embolization, segmental embolization and temporary embolization. A, direct embolization: for vascular hemangioma should be embolized from the distal branch of the external carotid artery, first embolization of the superficial temporal artery and internal maxillary artery, and then embolization of the external and external lingual artery. Temporary embolization A gelatin sponge powder immersed in physiological saline can be directly aspirated with a 5 ml syringe and injected into a contrast catheter. The permanent embolization can first absorb the saline, then insert the thread into the depth of the syringe nipple, cut at the tip of the nipple, and inject the contrast catheter. After injecting a certain amount, the contrast agent is "smoke" through the contrast catheter to observe the range and speed of blood vessel development. When the number of developing blood vessels is gradually reduced and the speed is significantly slowed down, it indicates that the embolization is effective, and the flow rate of the contrast agent can be continued to be slow, and the embolization is stopped when it is almost retained. The contrast catheter is retracted and inserted into the branch near the proximal end of the external carotid artery to continue embolization. When embolizing the branch of the external carotid artery near the bifurcation of the common carotid artery, it is necessary to frequently observe the blood flow velocity and the vascular development of the tumor area, and auscultation or percussion of the tumor area. If the embolization has been completed, stop it in time to avoid embolization of the material through the neck. The total arterial bifurcation flows retrogradely into the internal carotid artery. For larger arteriovenous fistulas, the microcatheter with microspheres can be placed through the contrast catheter, the fistula is blocked first, and the embolic material is injected to block the smaller arteries. This prevents the embolic material from flowing into the vein and embolizing the pulmonary vascular bed. It is also useful for permanent embolization of hemangioma with 5% cod liver sodium sulphate plus gelatin sponge powder, steel ring and other methods. B. Segmental embolization: For recurrent hemangioma of the external carotid artery that has been ligated in the past, it may occur that the branch from the ipsilateral vertebral artery and the branch of the lateral carotid artery establish a lateral branch for blood supply, in order to reduce intraoperative bleeding. The main part of the vertebral artery before the cranial artery must be staged embolization, that is, the upper and lower sections of the collateral branch established by the vertebral artery and the external carotid artery system are embolized to prevent serious complications and prevention of embolization of the vertebral artery. Retrograde blood flow. The method is to first place the microcatheter with microcapsules into the vertebral artery into the forefoot of the occipital bone, fill the balloon, block the upper segment of the vertebral artery, observe for 15 minutes, and release the balloon if there is no adverse reaction. Then, in the lower part of the vertebral artery trunk and the anterior branch of the external carotid artery, a microballoon is placed to block the vertebral artery, and the same observation is performed for 15 minutes. If there is an adverse reaction, such as numbness of the arm, headache, etc., the ball is adjusted. The position of the capsule; without adverse reactions, the microspheres are released. Thus, the thrombus formed between the two balloons can completely block the blood supply of the collateral vessels of the hemangioma, and the thrombus can play the role of fixing the microspheres, preventing the chronic leakage of the microspheres, and falling off after contraction. Severe complications occurred after rushing into the distal end of the vertebral artery. C, the closer the starting point of the blood supply artery of the hemangioma is to the proximal end of the external carotid artery, the greater the risk of embolization material entering the internal carotid artery. In order to prevent the embolization material from flowing back, a pedicled balloon can be placed at the beginning of the internal carotid artery to temporarily block the blood supply to the internal carotid artery, and then the external carotid artery and its branch embolization can be performed. Once the embolization is completed, the balloon can be withdrawn. Temporary interruption of the internal carotid artery should be released once every 30 minutes to prevent the cerebral ischemia time of the affected side from being too long. Embolization can also be performed with a tube microsphere. 6, wound treatment After the angiography and embolization, the contrast catheter and trocar were slowly withdrawn, and the puncture site was immediately pressed with gauze for 15 min until the blood was completely stopped, and the sand bag was used for 6 h. The patient can be placed in a supine, semi-recumbent or sitting position. complication 1. Hemiplegia, aphasia and death. 2, pulmonary embolism. 3. Skin necrosis.