What we can learn about stroke from a simple MRI technique

Using MRI scans to measure iron content can help specialists learn more about stroke-related damage to the brain, according to a new study published by Radiology. Should such measurements be required after patients suffer a stroke?

The researchers noted that degeneration in areas of the brain such as the substantia nigra (SN) is one long-term outcome that can come well after a stroke.

“Overall, the SN is strongly involved in motor control, but also in regulation of emotions, cognition and motivation,” study co-author Thomas Tourdias, MD, PhD, professor of radiology at the Centre Hospitalier Universitaire in Bordeaux, France, said in a prepared statement. “Usually, stroke doesn’t directly affect the SN but, by interrupting circuits, stroke can induce secondary degeneration of that area.”

The authors turned to the MRI technique known as R2* mapping, hoping it could measure iron contact within the brains of patients and show signs of long-term degeneration. Using it on 181 patients who had suffered a stroke, Tourdias et al. found that higher iron content in the SN was associated with “worse long-term outcomes, particularly when it was found on the same side of the brain that the stroke occurred.”

This finding “could be clinically useful because it shows that a simple magnetic resonance imaging method such as R2* can provide a more comprehensive picture of the consequences of an infarct,” Tourdias said in the same statement.

Does this confirm that iron imaging can be seen as a marker for degeneration in the brain? Should R2* mapping become a regular part post-stroke care for patients? Tourdias’s team is still assessing these questions, but he concluded that R2* mapping “could become crucial to the clinic” in the years ahead.