Trauma to the skull can cause serious damage to the brain, gray matter. They, in turn, can cause the development of severe and often irreversible ailments that threaten human life. Next, we consider one of these consequences - diffuse axonal damage to the brain, what it is, what a dangerous condition is like.
General information
First you need to give a brief classification of the stages of skull injuries:
- Easy. Such an injury is accompanied by a slight bruise and concussion.
- Medium. In this case, the degree of bruising is characterized as moderate.
- Heavy. At this stage, compression and diffuse axonal damage to the brain occur. Injuries in this case are inertial in nature.
Description
Diffuse axonal damage to the brain (DAP) is a large-scale destruction of the processes of nerve cells with small predominant hemorrhages. According to the clinical picture, a pathological lesion is formed at the border of gray and white substances. Diffuse axonal damage to the brain (DAP) significantly reduces the quality of life and mental activity of the victim. The patient's condition, without a doubt, can be considered serious. This is mainly due to the fact that there is a rather serious threat to his life. With a bruise, hematomas form, swelling develops, and a subdural hygroma appears . The outflow of cerebrospinal fluid from the ventricular zone is impaired; an impressed fracture is often detected. These phenomena occur before diffuse axonal damage to the brain develops. Injuries, as a rule, are so serious that far from all cases, it is possible to restore the previous activity of the organ. The victim himself rarely enough, as practice shows, returns to his previous normal state. After undergoing treatment and rehabilitation, a patient with diffuse axonal brain injuries should be regularly visited by a doctor. Inspections are necessary to monitor the condition of the body and timely detection of deterioration.
Diffuse axonal damage: symptoms, signs, diagnosis
How is the pathological condition manifested? Many brain lesions, diffuse axonal damage in particular, are accompanied by prolonged coma. This condition occurs immediately at the time of injury to the cranium. In addition, there is a significant change in muscle tone. Diffuse axonal damage is accompanied by meningeal syndrome and gross stem manifestations. A sharp decrease in pressure and collapse are noted. The patient ceases the activity of all the brain centers. The coma can be very long, the clinical prognosis in such a situation, as a rule, is not very favorable. There is a chance that the patient may die without regaining consciousness. With another development of events, the patient manages to get out of the coma, but after a sufficiently long time period. Unconsciousness can last 2-3 weeks. Coma may be accompanied by a change in the functions of the cerebral hemispheres. In this case, the patient experiences characteristic pain.
Vegetative state
Diffuse axonal damage to the brain is characterized by a rapid change in the clinical picture. So, a coma can go into a vegetative or transistor state. Clinically, diffuse axonal brain damage manifests itself in different ways. Moreover, some manifestations replace others with a fairly high speed. The vegetative state is characterized by functional uncoupling in the cerebral hemisphere. It can persist for several months. In the vegetative state, there are signs of a functional disorder in the subcortical-stem structures of the brain. Disorders in important processes provokes the appearance of bulbar, pupillary and other similar manifestations. With a change in muscle tone, late-tonic and incomprehensible defensive reactions occur. These include, in particular, cramps in the upper and lower extremities, an increase in amplitude during movements, tilting of the head, trembling of the hands, and complex postures of the body. As mentioned above, clinical manifestations change very quickly. For an hour, for example, various pathological reflexes can be noted. When revealing changes in the vegetative state, patients develop dyskinesia, atactic gait, and speech and mental disorders occur. Among the latter, it is worth noting aspotence, amnesia, and moral exhaustion.
The further course of the pathological process
Diffuse axonal damage to the brain is characterized by a logical transition from a prolonged coma to a stable transient vegetative state. This is indicated by new manifestations that did not exist before. So, for example, the patient may unnecessarily focus his eyes, blink, or respond to external stimuli. If the vegetative state lasts a long period, then new signs of the disease are detected. In particular, hypotrophy of carpal muscles, fibrillation of limb muscles is noted. In this case, the rapid progress of paroxysmal conditions is noted . They are represented by tachycardia, hyperemia, hypertension and other abnormal manifestations. Subsequently, deterioration is noted. Diffuse axonal damage to the brain is now accompanied by stiffness of muscles, discoordination, hypomyemia, oligophasia, bradykinesia, discoordination, and ataxia. Headaches are frequent for the patient. Vomiting syndrome begins to develop, difficulties arise with tilting the head and leg extension, stiff neck is noted. Many patients are characterized by hyperthermia (from the blows of the cortex there is a rather sharp increase in temperature), ptyalism, increased sweating. Thus, we can conclude that diffuse axonal damage to the brain provokes irreversible pathological processes in the organ.
Patient examination
Diffuse axonal damage to the brain is detected exclusively by MRI and CT. These research methods allow visual observation of an abnormal increase in organ volume due to hyperemia or edema with compression of the ventricles. Other exacerbated manifestations are also recorded. With the help of CT, specialists have the opportunity to assess the clinical picture and make an estimated prognosis for the future. MRI shows all the pathological changes caused by extensive or partial hemorrhages that accompany diffuse axonal damage to the brain. The degree of the pathological condition is also determined on the basis of magnetic resonance imaging. The results of the study allow choosing the optimal therapy for the patient. An accurate diagnosis is made on the basis of lumbar puncture. This procedure is extremely important for the timely detection of subarachnoid hemorrhages. Together with this puncture allows us to conclude that the predominance of high intracranial pressure. This procedure is contraindicated in patients with volumetric intracranial processes that cause brain dislocation.
Acute CT scans
Diffuse axonal damage to the brain is characterized by a pronounced or moderate increase in organ volume. There is also a narrowing, and in some cases a complete compression of the III and lateral ventricles, cisterns of the base and convexital subarachnoid spaces. Changes in tissue density, as a rule, are normo-sensitive, but increases or decreases can be noted. In the white matter, corpus callosum, stem and subcortical structures, small focal hemorrhages are often found. It should be borne in mind that the CT picture in patients may remain in the range of age norms. The dynamics in patients with diffuse axonal damage to the brain is characterized by the development of the atrophic process. In particular, ventriculomegaly, expansion in convexital and basal subarachnoid spaces is noted. At a later date after the injury (after about 3-4 weeks), an accumulation of cerebrospinal fluid in the frontal zones and the interhemispheric fissure (in its anterior sections in particular) can often be observed. It can be eliminated in the course of stabilization of mental and neurological status. This is indirect evidence of volume recovery after brain damage. Traumatic brain injury in children is much more often and better than in adults, amenable to therapy.
Conclusions on the results of CT
According to the picture, you can tentatively judge the absence or presence of intracranial hypertension. If the cisterns of the base and ventricle are not visualized on CT, or if there are manifestations of their gross compression, the probability of ICH is high. In this case, it may be quite reasonable to install a sensor for measuring intracranial pressure and its subsequent correction. If CT shows clearly the pathways of the outflow of CSF, especially from the ventricle and cisterns, ICP is most likely within the burrow. It is unlikely that measures aimed at reducing it will be useful for the victim. Patients have a significant disorder of osmotic homeostasis due to primary or secondary damage to the stem and hypothalamic-pituitary structures. In patients with a moderate hyperosmolar state, more favorable outcomes are noted, with a more pronounced death often occurs.
Pathogenesis
Macroscopic examination of tissues does not show destructive changes on the basal and external surfaces. Along with this, in the white matter there are areas of deep damage. Local hemorrhage zones in different parts of the brain can also be detected. A histological examination is also performed. It allows you to detect the presence of "axonal balls." These elements are areas of rupture in the nerve endings. In addition, histological examination reveals changes in cylinders of a destructive nature with appearing varicose thickenings. One month after the injury, balls disappear and macrophages proliferate in the alteration zone. Further changes in the myelin sheath occur, pathological processes in the neurons of the peripheral part of the nervous system continue. Also, lesions of the nerve fibers of the spinal cord and brain develop.
Therapy: General Information
For patients who have revealed diffuse axonal damage to the brain, a complex treatment is prescribed, which includes several methods. In particular, patients need a long mechanical ventilation (lung ventilation) in a moderate mode of hyperventilation. Complex therapy is prescribed, which includes the use of vasoactive and nootropic drugs, maintaining stability in metabolic processes using probe (enteral) and parenteral nutrition. Surgery, as a rule, is not prescribed, since there is no substrate to be removed. Surgical manipulations are advisable in detecting other progressive abnormalities that exert high pressure on the brain and its components. Due to the high incidence of extracranial complications (pulmonary and purulent-inflammatory, mainly), antibiotic and immunocorrective drugs are included in the therapeutic course.
Scheme of therapeutic measures
Patients with diffuse axonal damage to the brain are hospitalized in a hospital. The institution carries out a range of therapeutic and rehabilitation measures. The scheme, in particular, includes:
- Mechanical ventilation to maintain the stable functioning of the respiratory system.
- Probe Nutrition.
- Intensive drug therapy .
- Maintaining a normal water-electrolyte balance.
- In some cases, the use of neurotransmitters, biogenic stimulants.
- Therapeutic gymnastics, contributing to the resumption of the normal functioning of the limbs, the prevention of joint diseases.
- Speech therapy sessions to stabilize speech activity.
After the operation, a quick recovery period with prolonged hospitalization is necessary. To stabilize the functions of the central nervous system, compensate for impaired brain activity, accelerate the rate of rehabilitation, vascular and nootropic drugs are necessary. It may also require the use of biogenic stimulants, drugs that affect tissue metabolism, as well as, according to indications, neurotransmitters (Madopar, L-Dopa, Nakom and others) and anticholinesterase medications. With DAP, there is no need for hormone therapy.
Forecast
The probability of curing a patient with DAP will depend on the extent of damage in the axons, the presence of edema, the possibility of attaching pathological processes of extracranial departments. When carrying out an effective complex of therapeutic measures in short time intervals, a favorable outcome is more likely. In the case of continued prolonged coma, the risk of complications increases. With its lengthening, the probability of adverse outcomes increases, and accordingly, the possibility of recovery decreases. Of great importance is the depth of the coma. The heavier it is, the worse the outcome. The possibility of complete or partial restoration of lost mental functions during the regression of neurological disorders, even in cases of damage when a patient develops a vegetative position in the patient after a prolonged coma, lasting from several weeks to months, can be considered fundamental. This phenomenon may indicate the likelihood of reversibility and compensation of neurotransmitter and structural disorders that underlie persistent impairment of functional activity in the brain after diffuse axonal damage.