• Posted May 29, 2024

Light Therapy Might Help Heal Injured Brains

Near-infrared light pulsing into a person's skull appears to boost healing in patients with a severe concussion, a new study finds.

Patients who wore a helmet emitting near-infrared light displayed a greater change in connectivity between seven different pairs of brain regions, researchers report.

“The skull is quite transparent to near-infrared light,” explained co-lead researcher Dr. Rajiv Gupta, a radiologist with Massachusetts General Hospital in Boston. “Once you put the helmet on, your whole brain is bathing in this light.”

For the study, researchers tested near-infrared light therapy on 17 patients who'd suffered an injury to the head serious enough to affect their thinking or be visible on a brain scan.

Patients put on the light therapy helmet within 72 hours of receiving a traumatic brain injury, and researchers used brain scans to gauge the effects of the treatment. Another 21 patients put on the helmet but didn't receive light therapy.

The researchers focused on the brain's resting-state function connectivity, or the communication that occurs between brain regions when a person is at rest and not engaged in a specific task.

Researchers took brain scans a week after injury, two to three weeks post-injury and three months after injury.

“There was increased connectivity in those receiving light treatment, primarily within the first two weeks,” said researcher Nathaniel Mercaldo, a statistician with Massachusetts General Hospital.

“We were unable to detect differences in connectivity between the two treatment groups long-term, so although the treatment appears to increase the brain connectivity initially, its long-term effects are still to be determined,” Mercaldo added in a hospital news release.

The new study was published May 28 in the journal Radiology.

It's not clear exactly why near-infrared light might speed brain healing, researchers said.

Light therapy might boost brain cells' production of energy, help more blood flow through the brain or reduce inflammation caused by the injury, Gupta said.

“There is still a lot of work to be done to understand the exact physiological mechanism behind these effects,” said researcher Suk-tak Chan, a biomedical engineer at Massachusetts General Hospital.

Researchers expect more light therapy studies will be done in larger groups of patients for longer periods of time.

If these results are validated, Gupta says light therapy could be used to treat many other neurological disorders.

“There are lots of disorders of connectivity, mostly in psychiatry, where this intervention may have a role,” Gupta said. “PTSD, depression, autism: these are all promising areas for light therapy.”

More information

The Cleveland Clinic has more about light therapy.

SOURCE: Radiological Society of North America, news release, May 28, 2024