If you’ve had a brain magnetic resonance imaging (MRI), you may be alarmed to hear that it shows small white spots. These white spots may indicate a cause for concern, including strokes or multiple sclerosis (MS). However, there are also a variety of explanations that are not alarming, such as vitamin deficiencies or migraines.

If you have white spots, or white matter hyperintensities, on your brain MRI, your healthcare provider will determine the cause based on your medical history and doing an exam. Other diagnostic tests may be used to determine the number of spots, their size and appearance, and their location in the brain.

This article will look at common causes of white spots on a brain MRI, along with risk factors and treatment options.

What Are White Spots on a Brain MRI?

Spots on a brain MRI are caused by changes in the water content and fluid movement in the brain tissue. These changes happen when the brain cells are inflamed or damaged.

These spots (lesions) are easier to see on T2 weighted images—a medical term that refers to the frequency (speed) of the radio impulses that are used during the scan.

In an MRI report, the white spots might be described as:

  • “High signal intensity areas"“White matter hyperintensities” (lesions that appear bright white on certain sequences of MRI scans)“Leukoaraiosis” (a term that is used if the spots are thought to be caused by decreased blood flow"Nonspecific white matter changes”

Causes of White Spots on MRI

Small strokes are the most common cause of white spots on a brain MRI. Small strokes are often caused by blockages of small blood vessels due to high blood pressure or diabetes. Large strokes are usually caused by heart disease or carotid artery disease.

White spots can appear anywhere in the brain but are usually found in the white matter near the four cavities that contain cerebrospinal fluid (ventricles).

Sometimes, white spots are caused by silent strokes—small strokes that don’t cause symptoms. A silent stroke may not cause symptoms if you have enough healthy brain function to make up for the small area of brain damage.

Silent strokes often occur in deeper regions of the brain and are usually caused by the blockage of small blood vessels.

Other causes of white spots on a brain MRI include:

  • A brain tumor (such as lymphoma)
  • Vitamin B12 deficiency
  • Infections (such as Lyme disease or HIV)
  • Lupus
  • Migraine
  • Multiple sclerosis (MS)

Risk Factors for White Spots on MRI

Since most white spots on an MRI of the brain are from strokes, there are some stroke risk factors to keep in mind:

  • Hypertension
  • High cholesterol
  • Smoking
  • Unhealthy diet
  • Diabetes
  • Obesity
  • Heavy alcohol use

Other risk factors for white spots on a brain MRI include:

  • Increased age: A certain amount of white matter change in your brain is expected as you get older.Genetics: If you are of Hispanic or African-American descent, you are at higher risk of developing white matter lesions on your brain MRI.

How Are White Spots on the Brain Treated?

Sometimes, a white spot can go away after treatment for a condition like an infection or brain tumor. The spots may also temporarily get smaller and worsen later. This is often the case with chronic inflammatory conditions such as lupus or MS that flare up and then improve.

White spots on a brain MRI may shrink months after a small stroke. They can also get worse if your risk factors for strokes aren’t treated, leading to more lesions on the brain.

Working with your healthcare provider can help you understand your brain MRI findings and create a treatment plan to address the underlying cause of the white spots and prevent more from occurring.

Treatment may include prescription medications, surgery, or lifestyle strategies to build a healthier brain, such as a nutritious diet and exercise.

Summary

White spots on a brain MRI are not always a reason to worry. There are many possible causes, including vitamin deficiencies, infections, migraines, and strokes.

Other risk factors for white spots include getting older, race/ethnicity, genetics, obesity, diabetes, hypertension, and high cholesterol.

You can’t always prevent white spots on the brain but there are some steps you can take to protect your brain. This includes following your provider’s treatment plan, eating a diet that meets your nutritional needs, and staying physically active.

A Word From Verywell

It can be frightening to hear that there are white spots on your brain MRI.

The cause of these changes is complex, and you may need further testing. Sometimes, white spots on a brain MRI are only temporary or are a normal part of aging. When they’re caused by a condition like MS or a stroke, look to your provider for guidance about what to do next.

While the lesions themselves are not always treatable, there are a number of effective strategies that can reduce your chances of developing more spots in the future.