Cerebral venous malformation
Introduction
Introduction to cerebral vein malformation Cerebral venous malformation is also called cerebral venous hemangioma. Because of its abnormal shape, cerebral venous tumor still provides functional venous drainage for the corresponding tissue, so it is also called developmental venous anomaly. Venous malformations can be divided into superficial and deep. The superficial type refers to the deep medullary vein through the superficial medullary vein into the cortical vein, and the deep type refers to the subcortical region leading into the deep venous system. basic knowledge The proportion of illness: 0.004% Susceptible people: no special people Mode of infection: non-infectious Complications: cerebral venous malformation
Cause
Cause of cerebral venous malformation
(1) Causes of the disease
Most people think that cerebral venous malformation is a congenital disease, which is caused by normal embryonic developmental disorders. In the 45th day of pregnancy, there are many structures in the brain of the brain called "venous jellyfish head", which are composed of dilated central vein and many small deep medullary veins. Composition, 90 days of gestation, these vein structures develop into shallow and deep venous systems. If the normal development of the vein is blocked, the early form of venous drainage is preserved. There is also a partial obstruction of the developing cortical venous system, causing compensatory dilation. Venous, cerebral venous malformations are often accompanied by cavernous hemangioma or other vascular malformations, suggesting that hemodynamic changes such as increased local blood flow may induce venous malformations, whether congenital or acquired, most people think that cerebral venous malformation is the brain The venous system is a normal compensatory variant, not a pathological change.
(two) pathogenesis
Cerebral venous malformation is mainly located in the cerebral hemisphere or cerebellar hemisphere. About 70% of the lesions are located on the screen. The frontal lobe is the most common, accounting for 40%, the cerebellar hemisphere lesions are 27%, and the parietal or occipital lobe lesions are 15%. And the thalamus accounted for 11%, the lesion is mainly located in the subcortical white matter, often combined with AVM, cavernous hemangioma or facial hemangioma.
Cerebral venous malformation is composed of a number of abnormally dilated myeloid veins, which are composed of a central drainage vein. The shape is a spider-like shape. The medullary veins are from the periventricular area. The central drainage veins are dried to the superficial venous system or chamber. Subdural deep venous drainage; the underlying lesions are directly drained to the dural sinus, the central drainage venous trunk is thicker than the normal vein, under the microscope, the deformed blood vessels are veins, the tube wall has few smooth and elastic tissues, and the tube wall can also occur. Transparent and thickened, normal brain tissue scattered between blood vessels, no abnormal arteries in the lesion, few thrombosis, hemorrhage or calcification, normal brain tissue between blood vessels, these characteristics are significantly different from other cerebrovascular malformations, such as AVM, cavernous hemangioma and telangiectasia.
At present, most scholars believe that cerebral venous malformation is caused by abnormal changes in congenital normal drainage vein. The evidence supporting this view is:
1 The disease has been found in infants and young children.
2 There are no other normal drainage veins in the anatomically located tumor.
3 When the lesion is removed during surgery, the brain tissue of the corresponding drainage area immediately undergoes congestion and swelling.
Prevention
Cerebral venous malformation prevention
1, should choose a light, high-protein, high-calorie, easy to digest, rich in crude fiber low-fat diet.
2, eat more crude fiber food, keep the stool smooth.
3, quit smoking and alcohol, fasting spicy, cold and other irritating foods and excitatory drinks.
4, fasting 8 to 10 hours before surgery, banned drinking for 6 to 8 hours.
5, 6 hours after anesthesia awake, no swallowing disorder can enter a small amount of liquid diet, and gradually changed to soft food.
6, patients with high blood pressure, adhere to the medication under the guidance of a doctor. Do not arbitrarily change the dose or stop taking the drug to avoid blood pressure and induce bleeding.
Complication
Cerebral venous malformation complications Complications Cerebral venous malformation aneurysms
The most common with cavernous hemangioma, the literature reports that 20% to 30% of cavernous hemangioma with venous malformation, the standard of histological distinction between the two is the presence of normal brain tissue and the size of the lumen of the vessel. Cerebral venous malformations can also be associated with other vascular or non-vascular lesions, such as tumors, demyelinating diseases, aneurysms, AVM, dural arteriovenous fistula, moyamoya disease, and vascular lesions of the head and eye, and venous malformations are often drained away. The reflux of the normal brain tissue of these lesions, in a few cases, also drains the lesions themselves.
Symptom
Symptoms of cerebral venous malformation Common symptoms Chronic headache coma Cranial hemorrhage Unstable gaze Head sign sensation Disorder
Most patients have few symptoms or bleeding in the clinic, and often find the brain lesions by chance. However, the cerebral venous malformations in the posterior fossa often cause clinical manifestations. The symptoms occur depending on the location. There are many chronic headaches on the off-screen lesions. , epilepsy, dyskinesia or sensory disturbance, the under-the-spot lesions are mostly gait instability or other posterior fossa space occupying symptoms, cerebellar lesions are more likely to bleed, cerebral venous malformation bleeding is mainly intracerebral and intraventricular hemorrhage, the main clinical manifestations Have:
1. Epilepsy: is the most common clinical manifestation, mainly for epileptic seizures.
2. Localized neurological dysfunction: manifested as unilateral limb paralysis, may be associated with sensory disturbances.
3. Chronic headache.
4. Intracranial hemorrhage: It is generally believed that the bleeding rate of cerebral venous malformation is 15% to 20%. The under-the-spot lesion is more likely to bleed than the on-screen lesion, and the patient suddenly has severe headache, coma or hemiplegia.
Examine
Examination of cerebral venous malformation
1. Cerebral angiography: The lesion is only developed in the venous phase. It can be seen that several dilated medullary segments are assembled into an expanded central venous trunk, from the central venous trunk to the superficial venous system, deep venous system or dural sinus drainage, no Abnormal arteriovenous stenosis signs, arterial phase and cerebral blood flow cycle time is normal.
2. CT scan: more normal scan, on the enhanced scan, a thick line of enhanced brain flow in the brain parenchyma to the cortex and deep brain, no edema around the mass and mass occupying, sometimes can also be expressed as a round spot This thick line or dot shadow is an image of the central venous trunk.
3. MRI scan: its performance is similar to that seen by CT. The lesions are low on T1-weighted images, high on T2-weighted images, and few on low-signal. The lesions show typical radiographic stars after injection of contrast agents. Or spider-like.
Diagnosis
Diagnosis and differentiation of cerebral ven
According to the clinical manifestations and typical venous vascular malformations in the performance of angiography, CT scan, MRI scan performance, generally can make a diagnosis.
Attention and phase differentiation, cerebral arteriovenous malformation is characterized by sudden subarachnoid hemorrhage under the age of 40, history of epilepsy or hemiparesis before hemorrhage, aphasia, history of headache, and no obvious increase of intracranial pressure, cerebrovascular Contrast, CT and MRI are helpful for identification.
