chronic epidural hematoma
Introduction
Introduction to chronic epidural hematoma Chronic extradural hematoma is rare, and it refers to hematoma that occurs 2 to 3 weeks after the injury. In general, more than 13 days after injury, hematoma begins to have calcification as a basis for the diagnosis of chronic hematoma. This disease is more common in young men, probably because the dura mater is attached to the skull without women, children and the elderly. It is easy to peel off. The predilection site is exactly the opposite of acute epidural hematoma, that is, it is located at the front, the top, the occipital, etc., and the crotch is less. The reason is that the hemorrhage of the ankle is easy to cause cerebral palsy, so the course of disease develops rapidly. basic knowledge The proportion of sickness: 0.8% Susceptible people: more young men Mode of infection: non-infectious Complications: cerebral palsy, fracture
Cause
Causes of chronic epidural hematoma
(1) Causes of the disease
The injury factors of chronic epidural hematoma have no special difference with acute ones. The difference is that the patient can tolerate hematoma for a long time after injury, and the clinical symptoms are very slow, which may be related to the size of the hematoma. The speed, the location is related to the compensatory capacity of the patient's cranial volume, so there is a saying that bleeding originates from the vein. In addition, some people think that it is caused by rupture of the meningeal artery aneurysm caused by trauma.
A few cases of delayed epidural hematoma can be found clinically: there is no obvious imaging abnormality on the first CT scan, but hematoma is found only after CT scan again after several hours or even more than ten days. This refers to the time or course of hematoma. Rapid, accounting for 5% to 22% of the total epidural hematoma, more male youth, may be due to the presence of dura mater hemorrhage in the head trauma, but due to brain tissue edema after injury, other formed with this Hematoma and some factors that cause increased intracranial pressure have formed a tamponade effect and have an oppressive effect on the hemorrhagic source, but later used excessive ventilation, strong dehydration, control of cerebrospinal fluid leakage, removal of intracranial hematoma and surgical decompression, etc., or Due to the influence of systemic hypotension, the intracranial hypertension is rapidly reduced, and the tamponade effect is suddenly lost. Therefore, the dura mater is peeled off from the skull, and the sputum causes delayed epidural hematoma.
(two) pathogenesis
The mechanism of chronic epidural hematoma is still unclear. Most people use bleeding rate to explain the process of hematoma formation. Gallagher (1968) puts forward the idea of "venous hemorrhage". He believes that the anatomical position of the meninges is more vulnerable than the middle meningeal artery. Burres (1979) also found that the arteries were intact during chronic epidural hematoma, so he agreed with this view. Iwakuma (1973) suggested that in pediatric cases, subarachnoid hemorrhage can be fractured and fractured. The epidural space is connected, which is one of the mechanisms for the formation of chronic epidural hematoma, because almost all cases of epidural hematoma have a skull fracture, but Ford (1963) believes that venous hemorrhage can not cause dural peeling, so he does not agree The view of "venous hemorrhage", Clavel (1982) believes that the location of the hematoma is the most important cause of chronic epidural hematoma, epidural hematoma occurs in uncommon areas, because the dura mater and the skull are tightly combined, which is difficult Rapid formation of hematoma in a short period of time, he believes that the use of "bleeding source" to explain the occurrence of chronic epidural hematoma is not comprehensive, because in a considerable part of chronic epidural There was no clear source of bleeding in the swollen patients. Mclaurin and Duffner (1993) considered that the location of the hematoma, the size of the hematoma, the compensatory effect of the cranial volume, the fracture of the skull and the tolerance of the individual were the main factors for the formation of chronic epidural hematoma. The source of bleeding is secondary, because 52% to 67% of chronic epidural hematoma is located at the top of the forehead. The bleeding source in this area is mostly venous sinus, platelet venous hemorrhage, intracranial pressure caused by slow bleeding process. Increased can be compensated for the discharge of cerebrospinal fluid. Here, the dura mater is tight, and it is difficult to form a hematoma rapidly. In addition, epidural hemorrhage can be reduced or absorbed through the substomach or subcapsule of the skull fracture, and the skull fracture Occurrence of hemorrhage caused by dural dissection at the same time, the formation of chronic epidural hematoma can explain the reasons for the failure to find a source of bleeding in some cases. In addition, it has been suggested that traumatic pseudo-meningeal aneurysm rupture is also a chronic dura mater One of the causes of external hematoma was the review of 14 cases of pseudo-meninged aneurysm rupture and epidural hematoma, both of which showed subacute or chronic processes.
Chronic extradural hematoma usually forms a blood cell agglomerate at an early stage, and forms a layer of granulation tissue on the local dura mater. These granulation tissues can be shown on CT. Only a few chronic hematomas form a capsule and central liquefaction, but For a long time, it usually takes about 5 weeks.
Prevention
Chronic extradural hematoma prevention
1. Patients with head injuries should be vigilant. Regardless of the serious injury, they should go to the hospital for treatment in time. Generally, X-ray head radiographs can be diagnosed by CT examination. Patients with acute illness should be operated promptly to remove hematoma.
2. If the patient is treated properly, without serious complications, the prognosis is good.
Complication
Chronic epidural hematoma complications Complications cerebral palsy
The disease, such as hematoma, continues to increase, can cause cerebral palsy, skull fractures and so on.
Symptom
Chronic extradural hematoma symptoms Common symptoms Sleepiness nausea and vomiting consciousness disorder coma breathing slowing irregular intracranial pressure increased pupil abnormal cerebral palsy
It is more common in young males. The predilection site is similar to acute or subacute epidural hematoma. It is located in the frontal area, the top area, the occipital area, etc., and is located in the sputum area. The course of the disease is generally 12 to 180 days, with an average of 25 Days, can be asymptomatic or intermediate awake period for several months, years, or even decades, the on-screen chronic epidural hematoma often manifests as progressive headache, nausea and vomiting, mild sleepiness, eye movement, trochlear nerve paralysis, Optic disc edema and hemiplegia, behavioral disorders, etc., the under-the-shoulders are mainly characterized by neck pain and cerebellar nerves in the posterior group.
In general, there are three symptoms:
1. Consciousness disorder: There are five types of consciousness changes after the patient is injured. 1 is always awake after injury; 2 has been comatose after injury; 3 is conscious after waking; 4 coma immediately after waking; 5 after waking after injury In the middle of the waking period, then coma.
2. Neurological symptoms: There are fewer signs of nervous system in the early stage, and only when the hematoma is pressed into the brain function area, the corresponding symptoms are manifested. However, if the cerebral palsy is caused by continuous increase, the pupil dilated can be expressed on the affected side. Typical signs such as paralysis of the contralateral limbs.
3. Increased intracranial pressure: As the volume of hematoma increases, patients often have headaches, vomiting is intensified, and Cushing reactions occur, such as increased blood pressure, weakened pulse, great power, and slow breathing.
Examine
Examination of chronic epidural hematoma
1. X-ray: Most patients have skull fractures, and the fracture line often crosses the dural vascular sinus or sinus.
2. CT scan: Chronic epidural hematoma occurs almost on the screen, and mainly occurs in the forehead, top, CT scan shows the fusiform high-density shadow on the brain surface, most chronic epidural hematomas in the CT scan double The convex lens has a low-density shadow, a smooth perimeter, and the edge can be enhanced. It can also be equal density or high-density shadow. Enhanced CT scan can reduce the rate of missed diagnosis and strengthen the chronic epidural hematoma in CT. In addition to the strengthening of the dura mater in the hematoma, it is also related to the formation of vascular granulation tissue rich in blood vessels on the outer surface of the dura mater. The hematoma may also have calcification or ossification. The vast majority of patients have skull fractures, and the incidence is higher than acute. Epidural hematoma is higher in the literature. The incidence of combined skull fractures is between 75% and 100%, with an average of 93%.
3. MRI: MRI diagnosis of chronic epidural hematoma has its own characteristics, especially the detection rate of small and thin chronic epidural hematoma is higher than that of CT. The typical cases are characterized by sharp boundary on both T1 and T2 images. Fusiform epidural high signal zone.
Diagnosis
Diagnosis and diagnosis of chronic epidural hematoma
At present, most people think that it is most reasonable to diagnose chronic epidural hematoma with head trauma for 12 to 14 days, because at this time, hematoma can be found under the microscope, and subacute epidural hematoma (48h to 13 after injury). In the day, there is no histological change of hematoma, and the diagnosis can be made in combination with clinical manifestations and imaging.
The diagnosis of chronic epidural hematoma depends on imaging examination. Most patients have skull fractures, and the fractures often cross the dural vascular sinus or sinus. The typical performance of CT scan is the fusiform high-density shadow on the brain surface. The perimeter is smooth, the edges can be enhanced, and occasionally calcification, MRI is a sharp-shaped fusiform high-signal region on both T1 and T2-weighted images.
The clinical features of chronic epidural hematoma are mainly headache, vomiting and optic disc edema. The patient can be in a state of chronic intracranial hypertension for a long time. If not carefully examined, it is often misdiagnosed as post-traumatic syndrome until the nerve is caused by intracranial hypertension. Systematic positive signs, such as disturbance of consciousness, hemiplegia, pupillary abnormalities or eye signs, are taken seriously, and can be distinguished from each other according to the course of disease and imaging findings.
