Types of Brain Injury

Brain injury can be acquired in a number of ways:

• Traumatic brain injury (TBI). This is the most common cause of brain injury and occurs when someone receives a blow to the head, for example, from a fall, a road traffic accident, an assault or a sporting injury. Boxers are often said to be 'punchdrunk', but their symptoms, such as slow cognitive functioning and slurred speech, are effectively due to an injury to the brain, received from persistent blows to the head.

• Brain haemorrhage. If not discovered early, the bleeding to the brain caused by a brain haemorrhage can result in significant pressure on the brain and consequent damage to brain cells. In some cases the damage caused can be quite serious.

• Brain tumour. Again the pressure caused by a tumour will cause damage and the larger the tumour the more damage will be caused. Brain injury may also result from the surgery which is undertaken to remove a tumour.

• Stroke. This is a form of brain injury which affects a very specific part of the brain, causing easily recognisable symptoms.

• Hypoxia. Brain injury is caused by hypoxia when the supply of blood to the brain, and therefore oxygen, is interrupted or restricted. This can happen in a whole variety of ways, including carbon monoxide poisoning, excessive bleeding, choking, suffocation, cardiac arrest, and as a complication of general anaesthesia. The longer the brain is deprived of oxygen the greater the damage that is caused.

• Disease. Certain diseases, such as meningitis, AIDS and encephalopathy can cause irreparable damage to the brain.