One step closer to in-vivo CTE diagnosis

Doctors are one step closer to diagnosing and treating chronic traumatic encephalopathy (CTE), thanks to an innovative imaging strategy developed at UCLA and UCSF. Researchers found a tentative link between brain shrinkage and CTE, using a volumetric MRI program called Neuroreader.

Cyrus RaJI, MD, PhD, and David Merrill, MD, PhD, measured the volume of more than 40 brain areas in a former high school football player, during two scans separated by four years. The 51-year-old subject estimated he received a half a dozen “noticeable” hits to the head per game, with at least one major concussion. He was diagnosed with ADHD and bipolar disorder in his late 30s and has experienced worsening symptoms, but he has adopted a healthy diet and exercise regimen in an effort to stave off neurodegeneration.

When comparing his past and present MRI, researchers found the subject’s brainstem had shrunk by 14 percent over four years, causing significant cognitive impairment. The shrinkage is tentatively linked to the presence of tangled tau proteins, a hallmark of neurodegenerative disease and one way to diagnose CTE.

The buildup of these proteins eventually destroys neurons, reducing brain mass. A true diagnosis can only be made by examining the brain tissue post mortem, but all signs point to CTE, rather than similar conditions such as Alzheimer’s, according to Raji.

“There’s a big inclination to diagnose early-onset Alzheimer’s when these symptoms present, but there was no shrinkage in the hippocampus,” he said. The hippocampus helps develop memories and is one of the first areas in the brain to be affected by Alzheimer’s. However, the subject’s hippocampus actually grew by 6 percent over the four-year period, preserving some of his memory function.

“One of the things that kept him from being institutionalized was his memory—even though he had problems on neurological tests, his memory was still normal."

This raises the possibility that a healthy lifestyle could help alleviate CTE symptoms—or that the post-retirement lifestyle for many NFL players is making it worse.

“Lots of ex-NFL players are engaged in harmful behaviors such as alcohol or drug abuse,” said Raji. “This healthy lifestyle component could be an important part of future brain rehabilitation programs.”

However, a fully-fledged rehabilitation program remains a distant goal. This research is still preliminary, and a large cohort study is required before any significant conclusions are to be drawn.

“We’ve never had entire teams come in and get scanned, to track the shrinkage over time,” said Raji. “These players might be reluctant to want to know, but at the same time, knowing earlier than later can provide more options for treatment.”

Read the article at the American Journal of Geriatric Psychiatry.