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Diffuse axonal injury

The term "diffuse axonal injury of the brain" (DAI) was first suggested in 1982 by J.H.Adams, and pathology itself as a separate form of CCT was first described in 1956 by S.J.Strich who observed patients being in the vegetative status . Such a type of trauma arises as a result of rotary acceleration-decceleration that happens in inertia types of trauma. It results in complete or partial damages (ruptures) of axons often combining with piecemeal hemorrhages . In most cases such changes in brain tissue take place in areas with the maximal difference of the density of brain tissue - on the border of the grey and white matter.

The clinical picture of DAI is characterized by a long-term comatose state which comes after trauma without a free-of-symptoms interval, symmetric or asymmetric decerberations (decortication), often - variability of changes of myotonus (from diffuse hypomyotonia to gormeotonia) rough truncal symptoms, the meningeal syndrome. In diffuse axonal injury of the brain one virtually always notes gross disorders of vital functions, as well as apparent vegetative changes. Coma is more frequenly transformed into the transitory or persistent vegetative status, in case of going out of which rough symptoms of prolapse are left (extrapyramidal symptoms and apparent disorders of psyche usually prevail).

Diagnostics of diffuse axonal injury is based on the account of biomechanics of craniocerebral trauma. The comatose state of the patient which ensued right after CCT, with the apparent disorders of truncal functions, generalized tonic reactions, the symptomatology which is symmetric or asymmetric in relation to decerebration (decortication) gives the ground to suppose preeminently DAI.

Computer tomography of the brain in DAI is characterized by the increase of the volume of the brain because of edema, swelling, hyperemia with the compres­sion of the ventricles of the brain and subarachnoid convexital spaces. At that, they often reveal microfocal hemorrhages in the white matter of the cerebral hemispheres, corpus callosum, as well as in subcortical and truncal structures.

MR] in DAI reveals changes depending on the presence or absence of hemor­rhages and their remoteness. A frequent finding of MRI-checkups in DAI are micro­focal hemorrhages in deep structures of subependymal. The intensity of the image of these foci goes down in the course of time.

Patients with diffuse axonal injury are not subjects to surgical treatment. Indications for the operation in DAI only arise in finding out concomitant focal damages causing concussion of the brain. Conservative treatment is carried out in departments of intensive therapy. The patients need performing a lomg-term ALV in the regime of hyperventilation with a complex of therapeutic measures aimed at the maintenance of metabolic processes with the use of enteral and parenteral, cor­rection of disorders of acid-base and water-electrolyte balance, normalization of the osmotic and colloid composition of blood, as well as of the system of homeostasis. For prophylaxis and treatment of infectious-inflammatory complications, they prescribe antibacterial drugs taking into account sensitiveness of microflora.

 


Date: 2015-01-02; view: 1145


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