hypothalamic injury
Introduction
Introduction to the damage of the hypothalamus Hypothalamic injury refers to a special clinical syndrome that occurs directly in the lower part of the thalamus due to a skull base fracture or a violent blow to the skull during the process of craniocerebral injury. It is characterized by abnormal activity of physiological functions such as internal organs, endocrine, material metabolism, body temperature regulation, maintenance of consciousness and sleep. basic knowledge The proportion of illness: 0.003% Susceptible people: no specific population Mode of infection: non-infectious Complications: brain contusion, brain stem injury
Cause
Cause of injury to the hypothalamus
Causes:
The lower part of the thalamus is deep above the skull of the skull. Therefore, the direction of violence directly or indirectly through the lower part of the thalamus may cause local damage. In addition, the area of the cerebellar incision may also involve this area.
Pathogenesis:
The lower part of the thalamus is an important subcortical center of the autonomic nervous system. It has an important relationship with the internal organs, endocrine, material metabolism, body temperature regulation, and maintenance of consciousness and sleep. Therefore, the clinical manifestations of the hypothalamic injury are often severe, and the subthalamic lesions are more severe. Less, mostly associated with severe brain contusion and/or brain stem injury. Usually, if the skull base fracture crosses the saddle or its vicinity, it often causes damage to the hypothalamus. When severe impact injury or contralateral brain injury causes the bottom of the brain When sliding along the vertical axis, it can also cause damage to the hypothalamus, and often involves the pituitary stalk and pituitary. The lesion pathology is mostly focal hemorrhage, edema, ischemia, softening and nerve cell necrosis, and even the pituitary stalk breaks and Bleeding in the pituitary.
Prevention
Hypothalamic injury prevention
The disease is a traumatic disease, pay attention to safety, drive carefully, keep the home environment bright, walk carefully, watch children and avoid trauma. Strengthening legal management: Strengthening law enforcement supervision and standardized management can reduce the incidence of craniocerebral injury. According to the experts' suggestions, some countries have passed legislation to force drivers and motorcycle drivers to wear helmets and safety belts. Drinking and driving are strictly prohibited. The internal airbags are regularly inspected. Those who violate the regulations are detained.
Multinational scholars have called for judicially mandatory bicycle drivers and athletes of certain programs to wear helmets, and violators must be detained by traffic police. In countries where adults are allowed to possess firearms, the system of squadrons must be strengthened. The increase in the number of vehicles should be coordinated with the improvement of transportation facilities.
Complication
Hypothalamic injury complications Complications brain contusion and laceration brain stem injury
In the lower thalamus, it can cause gastric and duodenal mucosal erosion, necrosis, ulcers and hemorrhage, often accompanied by severe brain contusion, brain stem injury or intracranial hypertension.
Symptom
Symptoms of hypothalamic injury Common symptoms Drowsiness, hypotension, urinary collapse, loss of water, dry skin, high fever, hypothalamic damage, sleep disorders, edema
1. Consciousness and sleep disorders
The posterior lateral region of the hypothalamus and the midbrain cap are both ascending reticular activation systems, which are the active mechanisms for maintaining arousal. They are important for managing arousal and sleep. Once damaged, the patient can develop symptoms of drowsiness, although it can wake up. However, the spins fall asleep again, and in severe cases, they may appear to be drowsy.
2. Temperature regulation disorder
The hypothalamus has a body temperature regulation function. When the anterior part of the thalamus is damaged, the body's heat dissipation function is impeded, and central hyperthermia may occur. The body temperature often rises suddenly, up to 41 ° C or even 42 ° C, but the skin is dry and sweatless, and the skin temperature is unevenly distributed. The limbs are lower than the trunk, and there is no inflammation and poisoning performance, and the antipyretic drugs are also ineffective; the posterior injury has a hypothermia caused by the failure of heat production and heat preservation: if the joint nodules are damaged, the body may have metabolic disorders and body temperature. It will be further reduced, such as extensive damage in the lower part of the thalamus, and the body temperature will rise and fall with the ambient temperature.
3. Endocrine and metabolic disorders
(1) The lower nucleus of the hypothalamus, the paraventricular nucleus or the pituitary stalk is affected by the pituitary gland, causing the synthesis and release of vasopressin, causing central urinary collapse. The daily urine output is 4000-10000ml or more. Below 1.005.
(2) dysfunction of the hypothalamic-pituitary-target gland axis, which may cause disorders of sugar and fat metabolism, especially the disorder of glucose metabolism, which is characterized by hyperglycemia, often coexisting with water metabolism disorders, and the blood osmotic pressure of patients increases. There is no ketone body in the urine, the patient is seriously dehydrated, blood is concentrated, shock, hyperosmolar, high glucose, non-ketone coma can occur, and the mortality rate is extremely high.
4. Circulatory and respiratory disorders
There may be various changes in cardiovascular function after hypothalamic injury. Blood pressure is high or low, pulse can be fast or slow, but in general, low blood pressure, pulse velocity is more common, and volatility is large. If hypotension is combined If there is hypothermia, the prognosis is poor. The disorder of respiratory rhythm is related to the damage of the respiratory management center in the lower part of the hypothalamus. It is often manifested as slowing or even stopping of the respiratory tract. Acute central pulmonary edema can occur when the anterior region is injured.
5. Digestive system disorders
From the anterior region of the hypothalamus to the dorsal nucleus of the medulla oblongata, there is a nerve bundle that manages the autonomic nerves of the upper digestive tract. Any damage to the upper digestive tract can cause upper gastrointestinal lesions. Therefore, when the severe traumatic brain injury involves the lower part of the thalamus, it is easy to cause stomach. Intestinal mucosal erosion, necrosis, ulcers and hemorrhage, the cause may be vasoconstriction of the upper digestive tract, ischemia; or excessive excitement due to vagus nerve; or hypersecretion of gastrin, gastric acid is too high, in addition to this Patients often suffer from intractable hiccups, vomiting and bloating.
6. Local neurological signs
Mainly the signs of cranial nerve involvement near the saddle area, including the optic nerve, optic tract, and trochlear nerve.
Examine
Examination of damage to the hypothalamus
1. Head X-ray film examination
Suspected skull fractures should be positive, lateral position, occipital force injury plus the amount of occipital position (Tang's position), concave fractures, tangential position, suspected optic nerve injury, optic nerve hole, orbital fracture Take a Koch position.
2. Waist wear
Understand the degree of subarachnoid hemorrhage and intracranial pressure, severe intracranial hypertension or severe cerebral palsy signs are contraindicated.
3.CT scan
It is an important basis for assisting diagnosis of craniocerebral injury. It can show skull fracture, brain contusion, intracranial hematoma, subarachnoid hemorrhage, ventricular hemorrhage, gas skull, cerebral edema or brain swelling, and cerebral cistern and ventricle under pressure. Position deformation, mid-line structure shift, etc., CT examination should be performed when the condition changes.
4.MRI
Patients with acute craniocerebral injury usually do not have MRI, but have stable axonal injury, cerebral hemisphere bottom, brain stem, focal contusion and small hemorrhage, equal density subacute intracranial hematoma, etc., MRI Often better than CT scans.
Diagnosis
Diagnosis and diagnosis of hypothalamic injury
The isolated and limited primary damage of the hypothalamus is extremely rare. In the process of trauma to the skull, multiple sites often occur. Therefore, the diagnosis of hypothalamic injury is often interfered with by other brain damage. In clinical practice, With one or two manifestations of subthalamic injury, it is necessary to have the possibility of injury to the hypothalamus, especially when there is a skull base fracture in the saddle area and nearby, it should be more vigilant.
Subthalamic injury is often associated with severe brain contusion, brain stem injury or intracranial hypertension, clinical manifestations are complex, often mutual error, so less simple typical cases, as long as there are some signs of damage to the hypothalamus It can be considered to be accompanied by this injury. In recent years, CT and MRI examinations have significantly improved the diagnostic level of subthalamic injury. However, sometimes focal hemorrhage near the third ventricle is often difficult to display on CT images due to volume effect. Therefore, it is better to use MRI for the lower part of the thalamus, even if only small scattered spotted hemorrhage can be displayed, in the acute phase, it is a low signal on the T1-weighted image, and in the T2-weighted image, the signal is sub-acute and chronic phase T1. The hemorrhagic lesion on the weighted image is a clear high signal, which is more conducive to recognition.
