Definition of brain lesions
Brain lesions are abnormal areas of tissue in your brain. Most likely, you’ve learned that you have a brain lesion or brain lesions as an incidental finding after having a brain-imaging test — such as magnetic resonance imaging (MRI) or a computerized tomography (CT) scan — performed for some reason. On MRI images, for example, brain lesions appear as dark or light spots that don’t look like normal brain tissue.
If you’ve been diagnosed with something described as a brain lesion, it implies that the cause of the abnormal-appearing area cannot be diagnosed by the image alone, and further evaluation is necessary.
A brain lesion may involve small to large areas of your brain, and the severity of the underlying condition may range from relatively minor to life-threatening.
Causes of brain lesions
If you’ve been told that you have a brain lesion, speculating on a cause may prove fruitless until you and your doctor have more information. The brain lesion could be left over from an old, resolved condition or a sign of some harmless (benign) condition. Or, it could represent something more serious.
Sometimes, despite extensive testing, the cause of brain lesions remains unknown. Among the known possible causes of brain lesions are:
- Brain aneurysm
- Brain AVM (arteriovenous malformation)
- Brain tumor
- Multiple sclerosis
- Traumatic brain injury
When to see a doctor
If a brain lesion discovered during a brain-imaging test doesn’t appear to be from a benign or resolved condition, your doctor will likely seek more information from additional testing or consulting a specialist.
Your doctor may recommend that you see a neurologist for a specialized examination and, possibly, further tests. Even if a neurological work-up doesn’t result in a diagnosis, your doctor may recommend continued testing to reach a diagnosis or follow-up imaging tests at regular intervals to monitor the lesion.