Brain lesions: Causes, symptoms, treatments
A brain lesion is an area of tissue that has been damaged, for example, by injury, infection, exposure to certain chemicals, or problems with the immune system. In some cases the cause is not known.
What symptoms might indicate a brain lesion?
Symptoms of a brain lesion vary depending on the type, location, and size, of the lesion. Symptoms common to several types of brain lesions include the following:
What are the different types of brain lesions?
Although they share a common definition, injury or damage to tissue within the brain, brain lesions vary greatly. Here are some common brain lesions:
- Abscesses: Brain abscesses are areas of infection, including pus and inflamed tissue. They are not common, but they are life-threatening. Brain abscesses often occur after an infection, usually in a nearby area, such as an ear, sinus or dental infection. They can also appear after injury or surgery to the skull.
- Alzheimer's disease and other dementias: Alzheimer's disease and some types of dementia are another group of brain lesions. In these lesions, nerve cells die, leaving behind damaged areas of the brain. Gradually, brain function in those areas decreases.
- Arteriovenous malformations (AVMs): An AVM is a type of brain lesion that occurs during early development. Arteries and veins in the brain grow in a tangle and become connected by tube-like structures called fistulae. The arteries are not as strong as normal. The veins are often too wide because of the constant flow of blood directly from the arteries through the fistulae to the veins. These fragile vessels may rupture, leaking blood into the brain. In addition, the brain tissue may not receive enough blood to function properly.
- Cerebral infarction: Infarction refers to death of tissue. So a cerebral infarction is a brain lesion in which a cluster of brain cells have died. Most often, this brain lesion is caused by a stroke.
- Cerebral palsy: This type of brain lesion occurs early in a child's development, from before birth until the age of three. Cerebral palsy does not progress over time. The brain lesions affect the child's ability to move, which can also make communication and related skills difficult.
- Multiple sclerosis (MS): With this condition, the immune system attacks and damages the nerve linings in the brain and spinal cord. These lesions make it difficult for messages to be sent and received properly between the brain and the rest of the body.
- Tumours: Tumours are clumps of cells that grow abnormally from normal tissue. Some tumours in the brain are noncancerous, or benign. Others are cancerous and may start in the brain, or they may spread to the brain from elsewhere in the body. They may grow quickly or they may remain stable.