Preoperative embolization of meningiomas

Meningioma accounts for about 15% to 18% of intracranial tumors. Occurs in the sagittal sinus, cerebral palsy, cerebral convex surface, sphenoid ridge and lateral fissure, anterior cranial fossa and olfactory sulcus, saddle area, cerebellum, cranial fossa, cerebellar cerebral horn, ventricle, slope And the large hole area of the occipital bone. Meningioma is rich in blood supply. Manelfe divides the blood supply into four types: type 1 is a simple external carotid artery; type 2 is a combination of internal and external carotid arteries, mainly external carotid artery; type 3 is a combination of internal and external carotid arteries, with neck The internal artery is the main type; the type 4 is the simple internal carotid artery. Some meningioma and vertebral basilar artery participate in blood supply. Cerebral angiography is the primary means of understanding the blood supply to meningioma. Selective internal and external carotid artery and vertebral artery angiography through the femoral artery to understand the source of blood supply to meningioma, tumor staining, drainage vein, venous sinus involvement, and external carotid artery and neck through selective external carotid artery angiography There is no dangerous anastomosis between the internal artery and the vertebral basilar artery. It provides a reference for selecting the embolization route and superselecting the intubation to avoid dangerous anastomosis and prevent complications. Preoperative embolization of meningioma can greatly reduce the blood supply of the tumor, reduce the intraoperative bleeding, facilitate the operation, reduce the death and morbidity of the operation, and make the surgery that can not be operated in the past become operable, making it difficult to make the operation difficult. . Therefore, in recent years, intracranial blood supply is rich in meningioma, and preoperative embolization is generally used as an important auxiliary measure for surgery 3 to 7 days before surgery. Preoperative embolization materials for meningiomas often use solid particle emboli, especially gelatin sponge. The reason is: 1 material is cheap and easy to get, easy to master; 2 micro-plug size can vary from person to person, self-cut; 3 is absorbable. Embolization of meningioma is based on natural blood flow, plus the power of contrast injection or saline, bringing particles to the center of the tumor, embolization within the tumor, there is a fashion to embolize the main artery of the blood supply artery close to the tumor, such as embolization can reach There is almost no bleeding when surgically removing the tumor, and the embolization effect should be considered satisfactory. Other embolic materials such as Ivalon, freeze-dried dura mater, silk particles, NBCA, and coils have few balloon applications. Treatment of diseases: meningioma Indication Blood-rich meningioma, where the external carotid artery participates in the blood supply, can perform embolization before the external carotid artery blood supply, as an important auxiliary measure for surgery. Contraindications 1. Although the blood supply of meningioma is abundant, it is mainly for the internal carotid artery, and is mainly for the external carotid artery. 2. Although meningioma is rich in blood supply from the external carotid artery, there is a dangerous anastomosis between the branch of the external carotid artery and the internal carotid artery or vertebral basilar artery, and the superselective intubation catheter cannot avoid the dangerous anastomosis. Preoperative preparation 1. Patient Preparation 1 Learn more about the medical history, perform a comprehensive physical examination and a systematic neurological examination. 2 Those with a history of epilepsy were treated with antiepileptic drugs before surgery. 3 preoperatively according to the condition of the CT scan plus enhanced scan, MRI, MRA examination. 4 blood, urine routine, bleeding, clotting time, liver and kidney function, chest fluoroscopy, heart, EEG, etc. before surgery. 5 fasting before surgery, iodine allergy test, puncture site (such as the perineum) preparation skin, indwelling catheter. 6 Use a cloth strap to restrain the limbs. 2. Special instruments, medicine preparation 1116 needle or 18G needle; 2 diameter 0.89mm, length 40cm guide wire; 36F catheter sheath; 44F, 5F angiography catheter, 1 each, 6F guide tube 1 ; 5 with a three-way soft connection tube; 6Y with a valve connector, 1 two-way switch; 7 pressurized infusion bag 2 sets; 8 Magic-3F/2F catheter and micro-guide wire each; 9 gelatin sponge Several blocks. Surgical procedure 1. Transarterial puncture cannula is generally used for transarterial approach. The perineum and bilateral groin are routinely disinfected and sterile towels are placed. With 1% or 2% lidocaine in the right (or left) side of the inguinal ligament 2 ~ 3cm, the femoral artery pulsation is clearly layer by layer infiltration anesthesia, and the patient is neurologically anesthetized. The right femoral artery was inserted into a 6F catheter sheath. 2. 4F or 5F cerebral angiography catheter was inserted into the left and right internal carotid artery and vertebral artery by selective angiography through 6F catheter sheath to understand the blood supply source, tumor staining, drainage vein and sinus involvement of meningioma. , the external carotid artery blood supply and its risk of anastomosis with the internal carotid and vertebral basilar artery. 3. If the patient is an indication for preoperative embolization, the catheter is superselected into the blood supply branch of the external carotid artery and avoids dangerous anastomosis. If the common catheter can not achieve the purpose of superselective intubation, after the heparinization, the 6F guiding tube is replaced, and the Magic-3F/2F catheter is inserted into the superselective intubation through the 6F guiding tube. 4. After the successful selection of the intubation, the gelatin sponge is cut into pieces with scissors to make particles of <250 m, diluted with physiological saline or 40% contrast agent, and the gelatin sponge particles are aspirated with a 1, 2 or 3 ml syringe. Under surveillance, intermittent injection of the catheter, while paying attention to the patient's condition changes, each bolus 1-2 particles, that is, a saline injection, to prevent the particles from clogging the catheter, while intermittent injection of contrast agent to monitor the embolism, see The bolus is stopped when the flow rate of the contrast agent becomes slow or there is reflux. 5. Observe the embolization results by contrast catheter or guide tube angiography. 6. At the end of embolization, neutralize heparin with protamine as appropriate, pull out the catheter and catheter sheath, and puncture the site for 15-20 min. If there is no bleeding, cover the sterile gauze and compress the dressing. complication The main complication of preoperative embolization of meningioma is neurological dysfunction caused by microparticle reversal during injection or misplacement into the internal carotid artery through dangerous anastomosis. Mastering the pressure and speed of the bolus particle is the key to prevent backflow. Superselective intubation avoiding dangerous anastomosis is the key to prevent mis-embolization of intracranial artery. In addition, embolization of the external carotid artery may cause necrosis or healing of the scalp incision margin.