A brain lesion is an abnormality seen on a brain-imaging test, such as magnetic resonance imaging (MRI) or computerized tomography (CT). On CT or MRI scans, brain lesions appear as dark or light spots that don't look like normal brain tissue.

Usually, a brain lesion is an incidental finding unrelated to the condition or symptom that led to the imaging test in the first place.

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.


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.

Oct. 04, 2017