Indirect carotid cavernous fistula
Introduction
Introduction to indirect carotid cavernous fistula Indirect carotid cavernous fistula, the dural arteriovenous fistula (DAVF) involving the cavernous sinus, is a Barrow type B, C, and D type, which is relatively rare in clinical practice. basic knowledge The proportion of illness: 0.001% Susceptible people: no special people Mode of infection: non-infectious Complications: epilepsy dementia pseudoaneurysm cerebral infarction
Cause
Indirect carotid cavernous fistula
(1) Causes of the disease
The etiology of this disease has not yet been clarified. Some possible factors related to the disease include: changes in estrogen levels in the body, sphenoid sinusitis and cavernous sinusitis, vascular muscle fiber dysplasia, craniocerebral trauma and craniocerebral surgery.
(two) pathogenesis
1. Changes in estrogen levels in the body: This disease occurs in women, especially in menopause after 50 or 60 years of age or in pregnant women. The reason may be that the level of estrogen in the body changes, resulting in thinning of the blood vessel wall, decreased elasticity, and increased fragility. And the distortion of the expansion, coupled with the impact of blood flow gradually formed sputum, speculated that may be related to changes in estrogen levels in the body.
2. Sphenoid sinusitis and cavernous sinusitis: Under normal circumstances, some dural arteries and veins terminate near the wall of the cavernous sinus, emitting many tiny branches distributed in the dura wall of the sinus wall, and have an extremely rich network with the cavernous sinus. Traffic, when inflammation occurs in the sphenoid sinus or cavernous sinus and then causes embolism, venous return is blocked, and increased intra-sinus pressure can cause these reticulated traffic to open to form dural arteriovenous fistula. This hypothesis has been confirmed in animal models.
3. Vascular muscle fiber dysplasia: This disease is a congenital disease, the patient's blood vessel elasticity is poor, easy to rupture and form sputum.
4. Craniocerebral trauma and craniocerebral surgery: can cause indirect carotid cavernous fistula.
Prevention
Indirect carotid cavernous fistula prevention
Some indirect carotid cavernous fistulas can heal spontaneously and have a good prognosis. With the development of interventional embolization technology, the therapeutic effect has been greatly improved.
Complication
Indirect carotid cavernous fistula complications Complications, epileptic dementia, pseudoaneurysm, cerebral infarction
Indirect carotid cavernous fistula may be complicated by conjunctival edema, limited eye movement, diplopia, limb paralysis, epilepsy, dementia, etc. For arterial embolization, the main complications include:
1. Hematoma at the puncture site: The neck puncture cannula is critically ill after hematoma, and most of the current methods are safer femoral artery intubation.
2. Cranial nerve palsy: Due to thrombosis in the cavernous sinus or mechanical compression of the balloon, the involvement of the nerve is most common.
3. Pseudoaneurysm: After the thrombus in the cavernous sinus is basically formed, if the contrast agent in the balloon leaks prematurely and the balloon is retracted, an empty space is formed in the cavernous sinus that is the same size as the balloon and communicates with the internal carotid artery. Cavity, that is, pseudoaneurysm, asymptomatic patients do not need to be treated, generally do not enlarge or re-form the fistula, and most of them can be closed by themselves, and those who have symptoms can try spring coil embolization.
4. Cerebral infarction: excessive balloon or premature detachment of the balloon, or loss of thrombus on the catheter, or injection of fluid embolic agent, and drift of other embolic agents can cause local or even cerebral hemisphere cerebral infarction, aphasia, limbs Neurological dysfunction such as paralysis.
5. Brain hyperperfusion: Patients with long-term severe blood stealing, once the fistula is closed and the internal carotid artery remains unobstructed, the blood flow in the affected side hemisphere suddenly increases, and headache, eye swelling and other discomfort may occur, and intracranial hemorrhage may occur in severe cases.
Complications of venous embolization: The most common and most serious complication is blood flow to the cortical vein or superior ocular vein, causing intracranial hemorrhage and visual deterioration. If the ocular vein is acutely blocked, blood flow to the cortical vein occurs. Intubation can be embolized through the lower sinus to the cavernous sinus, occlusion of the fistula. Sometimes, the carotid cavernous sinus fistula may have acute visual loss after a period of embolization. Most of them will heal in a short period of time. Other complications include operation. Intravenous rupture, cerebral nerve palsy, and embolic agents flow back to the internal carotid artery system causing brain and retinal infarction.
Symptom
Indirect carotid cavernous fistula symptoms Common symptoms Increased intracranial pressure intracranial hemorrhage
The clinical manifestations of indirect carotid cavernous fistula depend on the location and size of the drainage vein, and have little to do with the blood supply artery. It can be clinically asymptomatic and can also cause fatal intracerebral hemorrhage. The most common clinical symptoms are:
1. Eyes: About 50%.
2. Intracranial murmur: 50% to 70% of patients will appear, the murmur is enhanced during strenuous exercise, and the common carotid artery murmur is reduced or disappeared.
3. Intracranial hemorrhage: can be expressed as subarachnoid hemorrhage, subdural hematoma or intracerebral hematoma.
4. Vision loss: About 27%, in severe cases, the patient is completely blind within a few hours; milder vision loss may be restored after treatment, but patients with complete blindness, even if the mouth is occluded, vision can not be saved.
5. Headache: It is also more common, which may lead to increased intracranial pressure caused by increased pressure in the cavernous sinus, or dilated arteriovenous stimulation of the meninges, compression of the trigeminal semilunar, and even a small amount of subdural or subarachnoid hemorrhage. Etc.
Most of the above symptoms are milder than direct sputum and the course of disease is slower.
Examine
Indirect carotid cavernous fistula examination
No special performance.
1. Cerebral angiography: The purpose of indirect carotid cavernous sinus cerebral angiography is to determine the location of the fistula, the blood supply artery, the venous drainage, the presence or absence of the external carotid artery system and the internal carotid artery system and the vertebral artery system. Dangerous anastomosis, etc., cerebral angiography includes selective angiography of the affected internal carotid artery, vertebral artery of the affected side, internal maxillary artery, pharyngeal ascending angiography, and selective contrast of the contralateral internal carotid artery and external carotid artery. Catheter superselective angiography can further understand the blood supply of each feeding artery.
Under normal circumstances, the cavernous sinus receives drainage of the superior and inferior venous and sphenoid sinus, and then through the rock, the lower sinus is drained to the transverse-sigmoid sinus junction and the jugular bulb, and the cavernous sinus on both sides passes through the intersponge sinus phase. In the presence of CCF, the pressure in the cavernous sinus is increased, and the direction of blood flow is changed: the venous vein is reversely flowed into the venous vein and the facial vein, the contralateral cavernous sinus is injected through the intersulcular sinus, and the sinus is reversed into the sphenoid sinus.
The blood supply of such carotid cavernous fistula is usually very complicated. Before the transarterial embolization treatment, cerebral angiography must be carefully studied, paying special attention to the presence or absence of "dangerous anastomosis". The condition of the common carotid bifurcation is also the brain. An important aspect of angiography to observe, if there is atherosclerotic plaque there, it is forbidden to treat indirect carotid cavernous fistula by compressing the common carotid artery.
2. CT and MRI scan: It can show dilated intraocular veins and other secondary changes in the eye, and can also find cerebral edema and intracranial hemorrhage; MRI can be found in the mouth near the dura mater with "flowing" phenomenon.
Diagnosis
Diagnosis and diagnosis of indirect carotid cavernous fistula
Indirect carotid cavernous fistula is mainly caused by middle-aged and pregnant women. It often initiates a disease. The course of disease is generally longer and the development is slow. It may have headache, exophthalmos, intracranial murmur, vision loss and other symptoms. Diagnosis is generally not difficult. In addition to the secondary lesions such as exophthalmos, cerebral edema, and cerebral hemorrhage, CT and MRI can also show thickened ocular veins and cortical drainage veins. It is important to find the "airflow" shadow of the dura mater on MRI. Diagnostic significance, but negative CT and MRI examination can not rule out the disease, the diagnosis must rely on whole brain angiography.
Need to distinguish from arteriovenous malformation, sudden subarachnoid hemorrhage under the age of 40, history of epilepsy or hemiparesis before hemorrhage, aphasia, headache history, and no obvious increase in intracranial pressure, should be highly suspected arteriovenous Malformation, but a clear identification depends on cerebral angiography.
