Brain Damage

By Dr. Vishaal Bhat on Tuesday, November 20, 2007 with 0 comments

Injuries of the maxillo-facial region are often combined with brain damages (up to 80% at poly-traumas).

Closed brain damages are classified according to the classical Petit’s division (1773):

Concussion of the brain - commotio cerebri

It is a functional damage associated with a short or longer unconsciousness without a topical brain tissue damage. Patients suffer from nausea and vomiting. An amnesia about the injury can occur. Therapy consists of resting in bed and exclusion of eventual more serious brain damages. This injury does not leave any persisting effects.

Contusion of the brain - contussio cerebri

It is the brain tissue focal damage of a various degree, location and extent. It may be either single or multiple. Microscopic lesions, mainly small bleeding occur chiefly at the white brain matter. These lesions appear both at the place of a direct impact and on the opposite side - “par contre coup”.

Signs are as follows:

  • unconsciousness, usually longer than half an hour

  • focal neuro-topical signs according to the contusion site (hemiparesis, aphasia, failures of brain nerves)

  • psycho-organic syndromes, retrograde pre-traumatic and post-traumatic amnesia

  • hormonal disorders (diabetes incipidus)

  • subarachnoid bleeding

  • epileptic paroxysms

Compression of the brain - compressio cerebri

The major symptoms of the brain compression are lacks of consciousness. An injured person regains consciousness after an initial period of unconsciousness at the time of an accident, but after some time (free interval, lucid period) looses his/her consciousness again. During periods of consciousness, a subdural hematoma is gradually formed as a result of mixed arterial and venous bleeding from wounded brain vessels or bridging veins and venous sinuses. It appears mainly at frontal and temporal areas. Less frequently, an epidural hematoma is caused by rupture of a. meningica media or its branches. It is an arterial bleeding causing a hematoma very soon followed by unconsciousness resulting from brain oppression. The lesion needs to be treated neuro-surgically by the skull trephining, draining the hematoma and stopping bleeding. Brain compression may also result from a brain edema as a result of vasomotor damage and increased permeability of capillaries that cause accumulation of fluid at peri-cellular and peri-vascular spaces. The danger of brain edema lies at so called “cone” (brain cone), when the brain matter is pressed by an edema through tentorium and by its shifting, the mesencephalon or the cerebellum are pushed against the bony shell. In the latter case, the cerebellum is pushed into the spinal cord canal through the foramen occipitalae magnum resulting at oppression of the center of breathing.

Brain damages of enclosed types can be best diagnosed by a CT examination. This kind of examination can reveal serious injuries. It is followed by consultation with a neurologist, functional examination by EEG and tranquilization by medication. Prevention of an edema and a strict rest in bed are imperative. State of consciousness should be checked periodically by waking up the patient, as well as fluctuations of blood pressure, pulse and breathing.

Damages of brain nerves

These damages also occur with serious head injuries. These are mainly damages to oculomotor nerves attributable to lesions of the IIIrd , IVth, and VIth brain nerves (the upper - cerebral, orbital fissure syndrome). A divergent strabismus of one eye indicates a damage to the oculomotor nerve (IIIrd) on the same side, occurring with paralysis of muscles innervated by this nerve. Musculus rectus lateralis, which is innervated by the n. abducens (VIth) then pulls the eyeball to the side. On the other hand, the opposite - convergent - strabismus indicates damages of the abducens nerve. A total paralysis of the oculomotor nerve (IIIrd) is manifested by a divergent strabismus, mydriasis of the pupil and ptosis of an upper eye-lid. Turning of both eyeballs is an important indication of a serious damage to the brain stem or cortex. Pinching or interruption of the optical nerve (n. opticus) may happen inside the bony canal. It results at impaired vision of the particular eye and abnormal reactions of pupils. The facial nerves (VIIth) gets hurt quite often during large injuries; its branches are damaged more often rather than the central lesion. Other head nerves get damaged scarcely (the auditory and vestibular nerves, as well as the glossopharyngeal nerve, vagus nerve, hypoglossal nerve, and n. accessorius).

Category: Oro-Maxillo Facial Surgery Notes



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