Diffuse axonal injury is widespread injury to axons, a part of the nerve cells, in the brain that can occur from a head injury.
Nerve impulses leave nerve cells through a part of the nerve cell called the axon. In diffuse axonal injury, axons throughout the brain are damaged.
Muundo wa Kawaida wa Seli ya Neva
Seli ya neva (nuroni) inajumuisha sehemu kubwa ya seli na faiba za neva—kiendelezi kimoja kilichorefushwa (aksoni) cha kutuma impalsi na kwa kawaida matawi (dendraiti) za kupokea impalsi. Impalsi kutoka kwenye aksoni ya seli 1 ya neva huvuka sinapsi (makutano yaliyopo baina ya seli 2 za neva) hadi kwa dendraiti ya seli nyingine. Kila aksoni kubwa imezungukwa na oligodendrosaiti katika ubongo na uti wa mgongo na Seli za Schwann katika mfumo wa neva wa pembezoni. Utando wa seli hizi una mafuta (lipoprotini) yanayoitwa myelini. Utando umefungwa kwa kukaza kuzunguka aksoni, na kuunda ala yenye matabaka mengi. kifunika myelini kinafanana na mfuniko wa mpira, sawa na ule unaozunguka waya wa umeme. Vichocheo vya neva husafiri kwa haraka zaidi kwenye neva zenye vifunika myelini kuliko kwenye zile ambazo hazina. |
The usual causes of diffuse axonal injury include falls and motor vehicle crashes. Diffuse axonal injury can occur in the abusive head trauma (shaken baby syndrome), in which violent shaking or throwing of a baby causes brain injury. As a result of diffuse axonal injury, brain cells may die, causing brain swelling, increasing pressure within the skull (intracranial pressure). Increased pressure may compound the injury by decreasing the blood supply to the brain.
Diffuse axonal injury typically causes loss of consciousness that lasts for more than 6 and less than 8 hours. Sometimes the person has other symptoms of brain damage. Increased pressure within the skull may cause coma.
Computed tomography (CT) usually does not show signs of bleeding in the brain, so magnetic resonance imaging (MRI) is usually done to detect diffuse axonal injury.
Treatment of diffuse axonal injury is similar to treatment of other head injuries. For example, doctors make sure that breathing and blood pressure are adequate and take steps to keep pressure within the skull from increasing too much.
Surgery is not helpful.
(See also Overview of Head Injuries.)
