What Are These White Spots on the MRI?

Understanding a Common Finding on Brain MRI

Doctor examining CT scan on digital tablet
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If your doctor tells you there are “spots” on a magnetic resonance image (MRI) of your brain, your first reaction might be to panic. But how worried should you be about these white matter changes? There is no widely accepted guideline for what is “too much,” though most neurologists have their own personal opinion. Some degree of these changes is expected with age. Ignoring these lesions completely, however, is not the best course of action.

What Are the White Spots on Brain MRI?

These spots may be referred to as unidentified bright objects (UBO), high signal intensity areas (HSIA), white matter hyperintensities, and nonspecific white matter changes. White matter hyperintensities are often located next to the ventricles, and as the name implies, are found in the brain’s white matter. They are most obvious on T2 weighted scans.

What Causes White Spots on a Brain MRI?

Nonspecific white matter changes typically have more than one cause. These changes have been associated with problems such as stroke, cognitive decline, depression, and diminished physical function, such as walking. It is not clear that these lesions actually cause these problems, however. They may just signify a relatively diminished state of brain health overall.

Similarly, cardiovascular risk factors like high blood pressure (hypertension) also increase with age. As you get older, your blood vessels tend to harden and narrow. This narrowing can lead to heart problems like myocardial infarction or brain problems like stroke.

Are These Changes the Same as Silent Strokes?

The hyperintensities in your brain are likely in areas that would be caused by reduced blood flow. There’s some controversy about how the flow could be reduced. Some have viewed the lesions as being miniature strokes that never caused symptoms, as opposed to being full-fledged strokes, in which blood pressure totally and completely stops. If blood flow slowed instead of stopped due to local changes in your blood pressure, these regions of your brain would slowly and periodically have its oxygen supply reduced.

What Increases the Risk of These Signal Changes?

If you have hypertension, smoke, or drink alcohol heavily, you are at risk for arterial narrowing. Diabetes and obesity also increase your vascular risk. White matter hyperintensities have also been correlated with all of those risk factors. Similarly, factors that protect blood vessels, such as a healthy diet and exercise, are associated with fewer white matter changes in the brain as we get older.

Like many other signs of vascular disease, some people are more at risk for these signal changes on MRI than others. If you are of Hispanic or African American descent, you are more likely to have lesions than other populations. Women tend to have white matter hyperintensities than men, as well.

There tends to be some degree of heritability to these lesions. Many genes have been associated with these changes, though it’s not clear exactly how they are related.

While a certain degree of white matter change is expected as you age, that does not mean these changes are completely benign. Increased white matter hyperintensities are associated with higher risk of stroke and dementia, as well as higher mortality in general. The lesions themselves are unlikely to be causing problems. Instead, the risk factors that cause the lesions increase your chances of developing problems inside and outside the nervous system.

How to Stop Spots From Worsening

Your doctor can help you understand your MRI findings best. Rather than just focusing on these hyperintensities, your doctor can help you identify what risk factors might need addressing. Could your diet stand some improvement? Do you need to exercise more?

When looking at what factors seems to correlate most with these spots in the brain, high blood pressure seems to be the most strongly related. However, studies have had mixed results on how to best manage blood pressure in light of these MRI findings. Some studies show that treating blood pressure helps, and others show no clear benefit.

What's Next?

White matter hyperintensities are an extremely common finding in brain MRI, especially for older people. However, just because these spots are common does not mean they are completely benign. Having an increased number of hyperintensities has been associated with stroke, dementia, and other problems.

The cause of these changes is complex, but likely represents vascular changes that can be impacted by following the kind of advice we all know we should follow anyway. Keep your blood pressure under control, eat right, exercise, avoid smoking and only drink alcohol in moderation. By following this advice, you may not only address the spots on your MRI but more importantly, keep your brain and entire body healthy.

A Word From Verywell

It can be frightening to hear that there are findings on your scans that mean you have increased risks. But there are steps you can take to reduce your risks and improve your chance of good health.