MRI shows brain coping mechanism for post-concussion syndrome

MRI can show changes in the brains of those with post-concussion syndrome (PCS), possibly opening the door to improved PCS detection and treatment, according to a study published in the December issue of Radiology.

“Conventional imaging with CT or MRI is pretty much normal in mild traumatic brain injury (MTBI) patients, even though some go on to develop symptoms, including severe cognitive problems,” Yulin Ge, MD, of New York University School of Medicine in New York City, said in a release. “We want to try to better understand why and how these symptoms arise.”

Ge and colleagues designed a study that used MRI to look at the brain during its resting state, which involves connections among a number of regions and with the default mode network playing an important role. Default mode network alterations have been found in some psychiatric disorders, but Ge explained little is known about default mode network connectivity changes in MTBI.

For the study, 23 MTBI patients who had post-traumatic symptoms within two months of injury underwent resting-state functional MRI performed at 3T to characterize the default mode network. These images were compared with others taken in 18 age-matched healthy controls, and were correlated with neurocognitive tests and clinical performance.

Results showed that, compared with control subjects, patients with MTBI had significantly reduced connectivity in the posterior cingulate cortex and parietal regions, and increased frontal connectivity around the medial prefrontal cortex (MPFC). These opposing changes were significantly correlated, according to the authors.

“Increased MPFC activation has been reported previously in moderate and severe traumatic brain injury and is hypothesized to represent brain neuroplasticity operating in recovery and neural repair after injury. Our finding of a negative correlation between increased MPFC connectivity and neuropsychologic symptoms also supports the notion of increased usage of MPFC neural resources as compensation in response to the impaired neurocognitive function,” wrote Ge and colleagues.

The results also showed that reduced posterior connectivity correlated clinically with neurocognitive dysfunction, while increased frontal connectivity correlated with posttraumatic symptoms, such as depression, anxiety, fatigue and PCS.

The next step is to recruit additional MTBI patients for a longitudinal study aimed at developing a biomarker to monitor disease progression. “We want to do studies to look at the changes in the network over time and correlate these functional changes with structural changes in the brain,” Ge said. “This could give us hints on treatments to bring back cognitive function.”