Cerebral vascular malformation in children
Introduction
Introduction to cerebral vascular malformation in children Cerebrovascular malformation mainly includes cerebral arteriovenous malformations and cystic aneurysms. In childhood, they are the most common cause of primary subarachnoid hemorrhage (subarachnoidhemorrhage) in children. basic knowledge The proportion of illness: 0.13% Susceptible people: children Mode of infection: non-infectious Complications: convulsions and convulsions hydrocephalus congestive heart failure
Cause
Causes of cerebral vascular malformation in children
(1) Causes of the disease
Cerebral arteriovenous malformations occur most often in two parts: the great cerebral vein (also known as the large venous vein of Galen) and the cerebral hemisphere vein. The large cerebral vein is located in the lower posterior part of the corpus callosum and is joined by the left and right cerebral veins. It is a short, thick, thin and fragile vein trunk. The direction of travel is from front to back, and finally into the lower sagittal sinus. Continued into the straight sinus. The arteriovenous malformation of the great cerebral vein refers to the posterior cerebral artery or Intracranial arteries and cerebral venous venous fistulas cause arterial blood to flow directly into the venous blood, resulting in a series of symptoms. Most of the cerebral hemisphere venous malformations are located under the cerebral cortex, and the sites where the middle cerebral artery is supplied For many, other parts such as the basal ganglia, brainstem and cerebellum are also involved, and cerebral vascular malformations include telangiectasia, cavernous hemangioma and the like.
(two) pathogenesis
1. Cystic aneurysm: Due to the weak structure of the middle layer of the blood vessel wall, it gradually expands, causing a cystic mass, and its predilection site is the anterior part of the skull base artery, especially at the branch of the blood vessel, its size varies, when its diameter When it has reached 6~15mm, it often ruptures at the base of the aneurysm. After rupture, it can cause massive hemorrhage in the subarachnoid space. It can also cause hemorrhage in the subdural, brain parenchyma or ventricle, and hematoma can be formed locally. Brain tissue, and can coexist with aortic coarctation or congenital polycystic kidney.
2. Arteriovenous malformation: Also known as congenital arteriovenous fistula, it can be single or multiple in the cranium. The arteriovenous malformation is mainly due to the lack of capillary development between the arterial and venous systems, and the short circuit between the arteries and veins. The arteries in the lesion supply area are extremely enlarged, and even form an aneurysm-like malformation; the venous return around the lesion is not smooth, and the congestion is expanded. Under the influence of intravascular pressure, the deformed part gradually expands, and finally the nearby brain tissue is pressed, resulting in brain atrophy. And easy to cause bleeding.
Prevention
Prevention of cerebral vascular malformation in children
The cause of this disease is unknown, and there is no effective prevention method.
Complication
Pediatric cerebral vascular malformation complications Complications, convulsions and convulsions, hydrocephalus, congestive heart failure
Because the tumor is compressed or ruptured to the surrounding tissue, causing convulsions, paralysis or aphasia, due to increased intracranial pressure, the consciousness is gradually coma, accompanied by hematoma, hydrocephalus, neonatal congestive heart failure, difficulty breathing and cyanosis, infants can Obstructive hydrocephalus and psychomotor developmental delay, cranial nerve palsy, periodic migraine.
Symptom
Symptoms of cerebral vascular malformation in children Common symptoms Brain parenchymal hemorrhage Cerebral palsy Meningeal irritation Increased intracranial pressure Increased neck tonic sputum Myelinization Delayed vertigo Consciousness Disorder Nausea
1. Intracranial aneurysm: The clinical manifestation is due to the direct compression of the aneurysm to the surrounding tissue or the bleeding due to the rupture of the tumor. There is often no obvious clinical symptoms before the blood is emitted, only occasionally III, V and VI. Cerebral nerve palsy; or slight forehead or eyelid pain, before bleeding, can be suspected of unilateral ophthalmoplegia due to difficult to explain the disease, bleeding often often acute, visible severe headache, vomiting and neck stiffness and other meninges Stimulation of symptoms, and can be seen convulsions, hemiplegia, sputum or aphasia, etc., sick children can gradually become comatose due to increased intracranial pressure, such as bleeding in the subarachnoid space, sick children can be indefinite signs, and only meningeal irritation, because Bleeding may have absorption of heat, retinal hemorrhage can be seen in fundus examination, and small infants may have full anterior iliac crest, increased tension, and intracerebral or subdural hematoma may cause neurological signs according to the affected area, such as bleeding in the dumb area. The clinical manifestations are mild; the bleeding range is small, the vital signs can be normal, and the first bleeding patient can be partially or completely recovered, but the bleeding will be repeated in the future. Therefore, it should be as early as possible. Diagnosis and prompt surgical treatment.
Because CT and MRI examinations are simple, rapid, and non-invasive, they have a high accuracy in the diagnosis of intracranial aneurysms. The biggest advantage is that they can accurately display the whole picture. In the diagnosis of aneurysms, other lesions such as hematoma can be found. , hydrocephalus, etc., some people think that high-definition MRA can replace DSA, but in the dynamic display of the morphology of aneurysms, and the relationship between the arteries of the tumor, small angiography is particularly important for the diagnosis of multiple aneurysms.
2. Arteriovenous malformation of the great cerebral vein: It is a rare cerebrovascular malformation. According to the difference of the affected part and its size, the clinical symptoms are very different. The vascular malformation of the baby and the posterior fossa of the newborn is not uncommon; The vascular malformation in children is mostly located in the cerebral hemisphere on the upper side of the screen. This disease is common in the neonatal period and infancy. The disease has an early onset and has circulatory symptoms. It is worthy of clinical attention. According to the size of the arteriovenous shunt, the first time The age at which the symptoms appear, the clinical symptoms can be divided into the following three groups:
(1) Newborns: Most of the neonates have congestive heart failure, which is caused by a large amount of arterial blood flowing into the vein and the heart can not tolerate. The sick child may have difficulty breathing and cyanosis, and may also have hydrocephalus. And horror.
(2) Infancy: due to the obvious expansion of large cerebral veins, compression of surrounding tissues or stenosis of the aqueduct, causing secondary obstructive hydrocephalus, examination of the skull, scalp and facial venous engorgement, optic disc edema, Cardiac hypertrophy, head auscultation can be sustained, loud and limited murmur, in addition to sick children can have convulsions, nosebleeds and mental retardation.
(3) Larger children: due to traffic cerebral vascular rupture, common subarachnoid hemorrhage or parenchymal hemorrhage, neurological signs depending on the location of damaged brain tissue caused by bleeding, sick children can show headache, nausea, vomiting and Consciousness disorder, can also have dizziness, convulsions, aphasia or organic psychosis, physical examination of mild hemiplegia, cranial nerve palsy, eyeball protrusion, eyelid drooping, strabismus, pupillary reflex disappearance and optic disc edema, etc. The film can show increased intracranial pressure and can have curvilinear calcification. The diagnosis depends on continuous angiography of the cerebral vessels (mostly vertebral angiography). It can be seen that there is an aneurysm caused by arteriovenous fistula in the Calen vein area, and the proximal end is abnormally thick. The cerebral artery is supplied with a strong development, and the distal end has a dilated vein that is extremely dilated and detoured into the intracranial sinus.
3. Cerebral hemisphere venous malformation: Common in older children or young people, clinical manifestations have a long history of periodic migraine, until the occurrence of subarachnoid hemorrhage, the clinical features and vascular malformation position, The area where the middle cerebral artery is supplied is the most common. The first symptoms of the sick child are mostly limited sexual seizures, sometimes generalized to systemic seizures. It can last for several years, and the intramural murmur is more obvious, suggesting the possibility of vascular malformation in the brain.
Examine
Examination of cerebral vascular malformations in children
In patients with acute subarachnoid hemorrhage, cerebrospinal fluid examination showed bloody cerebrospinal fluid, and the pressure increased. After 1 to 2 weeks, the cerebrospinal fluid became yellow, white blood cells and protein were slightly increased, and the hematoma was not worn or huge cerebrovascular malformation. There is an increase in intracranial pressure.
Various auxiliary examinations can provide a basis for diagnosis, and cerebral angiography, brain magnetic resonance and pathological examination have the value of diagnosis.
1. X-ray head plain film examination: In some cases, calcification spots and vascular groove thickening are seen, and a few have increased intracranial pressure or pineal body displacement.
2. EEG examination: It has been reported that 90% of cases of cerebrovascular malformation show EEG abnormalities, mostly localized abnormalities, only a few are diffuse changes, EEG abnormalities are not related to the age and stage of the sick children, cerebral vascular malformations The range of diameter above 2 ~ 3cm or hematoma, EEG changes are more significant, the authors of epilepsy are more common, the deformity in the top temporal lobe is more limited than the occipital lobe and posterior fossa.
3. Imaging examination: It is an important method to define cerebrovascular disease and its location and extent.
(1) CT scan of the head and magnetic resonance imaging (MRI): MRA (magnetic resonance angiography) is a non-invasive angiography method, which is widely used in clinical applications and has a large cerebral vascular occlusion, stenosis and deformity. Diagnostic value, CT scan can often show calcification of arteriovenous malformation, cerebrovascular hemorrhage or hydrocephalus associated with hydrocephalus, such as small non-calcified CT scan in the brain can not be displayed, only by CT scan Vascular malformations or brain tumors are often difficult, but brain MRI does show that angiography does not detect abnormal images of small arteriovenous malformations.
(2) cerebral angiography: It can visually display the imaging characteristics of diseased blood vessels, so it has special diagnostic value for stroke. In the past two decades, the application of digital subtraction angiography has been increasing. The principle is to use digital computer programs to generate blood vessels. The X-ray examination method of imaging, because of the subtraction, the concentration of the contrast agent in the blood can be developed as long as it reaches 2% to 4%, which is much lower than that required for conventional cerebral angiography, and it is also for the cerebral blood vessels. The diagnostic value and development of sexually transmitted diseases are superior to conventional angiography, but may be unclear for small intracranial vessels.
Diagnosis
Diagnosis and diagnosis of cerebral vascular malformation in children
Clinical features and auxiliary examination features may aid in diagnosis, except for other intracranial lesions.
Different from other cerebrovascular diseases, such as intracranial hemorrhage, cerebrovascular embolism.
1. Cerebrovascular hemorrhage is most common in craniocerebral trauma, birth injury, sometimes thrombocytopenic purpura, aplastic anemia, hemophilia, leukemia, brain tumors, and acquired acquired late vitamin K deficiency. Can be complicated by cerebrovascular hemorrhage, clinical onset, convulsions, coma, convulsions, neck stiffness and symptoms of intracranial hypertension (such as severe headache, frequent jet vomiting, optic disc edema, slow pulse, high blood pressure, etc.), waist The cerebrospinal fluid is evenly red, the pressure is increased, and the red blood cells are contained. After a few hours, there are wrinkled red blood cells, which are easy to be complicated by hippocampus, and the cerebellar tonsils can cause rapid death.
2. Cerebral vascular embolism (cerebrovascular embolism) Infective endocarditis, rheumatic heart disease mitral stenosis with atrial fibrillation, cardiac wall thrombus can fall off causing cerebral embolism, occasional air embolism, complex open fracture Fat plugs, emboli of thrombophlebitis can also cause cerebral embolism. The clinical onset is sudden, sometimes only occurs within a few seconds. Because of easy to break into the middle cerebral artery, there are three partial signs, cerebrospinal fluid is normal, or there are slight red blood cells. Increased, acute stage may have mild disturbance of consciousness, but the period is shorter, the intracranial hypertension is mild, the distal part of the cerebral embolism has secondary cerebral edema and subsequent brain softening, lacunar infarction (lacunar cerebral infarction) And the cavity is easy to leave partiality, dementia.
3. Cerebral thrombosis (cerebrovascular thrombosis) tetralogy of Fallot, polycythemia vera, thrombocytopenia, diffuse intravascular coagulation and other blood viscous, can be complicated by cerebral artery thrombosis, clinical onset is relatively slow, prone to Light and moderate internal capsule triple deviation, the consciousness is not affected, the cerebrospinal fluid is normal and there is no red blood cells.
4. Cerebral endophthalmitis (cerebral endoarteritis) In the past, tuberculous meningitis, bacterial meningitis, leptospirosis and cerebral endarteritis are common, and connective tissue disease (especially systemic lupus erythematosus) is rare. After cryptococcal meningitis and non-specific virus infection, sometimes middle cerebral artery endarteritis is complicated, and hemiplegia syndrome occurs. The latter is mild, most of them return to normal after 1 to 2 months, and leptospirosis can cause Alternating hemiplegia or even bilateral paralysis occurs.
5. Occlusive eerebrovascular disease: Congenital or acquired cerebral unilateral or bilateral superior carotid artery in the upper segment of the cerebral artery, stenosis or progressive occlusion at the beginning of the siphon segment or anterior and middle cerebral arteries. A secondary majority collateral circulation was established to form a special abnormal vascular network. The angiographic image of the cerebral angiography was called Moyamoya disease. The sick child had vomiting, headache, hemiplegia, convulsion and disturbance of consciousness.
Kawasaki disease is a syndrome characterized by systemic and small arterial allergic inflammation. Occasionally, cerebrovascular occlusion or aneurysm and thrombosis may occur, but it is less common than coronary artery disease.
