What is a brain lesion?

An intracranial lesion or brain lesion is damage to the brain tissue because of illness, injury, disease or infection, or some other cause. The cause of a brain lesion is sometimes unknown. The lesions are often found during an MRI or CT scan being performed to test for or diagnose some other condition. The lesion shows up as a light or dark area on the brain. There may be just one or several, which may or may not produce symptoms, such as:

  • Headache
  • Change in vision or eye pain
  • Loss of memory, confusion
  • Nausea
  • Seizures

Some people with brain lesions also experience changes in mood, personality and behavior, depending on what area of the brain the lesion or lesions is affecting.

Types of brain lesions

There are different types of brain lesions, each with different characteristics. Some common types include:

  • Benign – Lesions that grow slowly and rarely affect surrounding tissue or become cancerous (malignant).
  • Traumatic – Lesions that develop due to traumatic brain injury or some other type of trauma to the head. Examples include hematomas and intracerebral hemorrhage.
  • Infectious – Lesions caused by a viral, bacterial or fungal infection (e.g., meningitis).
  • Malignant – Lesions caused by a cancerous tumor affecting surrounding tissue.
  • Vascular – Lesions that may develop congenitally (before birth) or may develop over time, often discovered by the time a person is in his or her 30s. Examples of vascular lesions include aneurysms, arteriovenous malformations (AVM) and stroke.
  • Immune – Lesions caused by a condition such as multiple sclerosis (MS), affecting the brain's ability to send signals.

Brain lesion treatment options

Depending on the type and cause of your lesion, treatment options vary and may include medication, surgical removal of the lesion, and in cases of cancer, radiation therapy and chemotherapy.



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