The news delivered this week in a Zoom call with Boston University’s Chronic Traumatic Encephalopathy Center came as no shock to Tommy McDonald’s family.

An autopsy on the brain of the Eagles Hall of Famer, who died at 84 in September 2018, revealed that he suffered from Stage 4 CTE, the most advanced form of the brain disease that continues to plague NFL players.

“It wasn’t surprising at all,” McDonald’s son, Chris, said Wednesday. “He showed all the symptoms.”

According to Ann McKee, the director of the BU center, where the brains of hundreds of deceased football players have been studied, McDonald’s disease was “as severe as it gets.”

“What I found was classic for long-standing CTE,” the physician said in a phone interview. “It had all the characteristic lesions around vessels involving a considerable extent of the brain.”

Closely associated with the kind of repeated head-banging typical in football, CTE has become an epidemic in the sport. McDonald was one of 4,500 former players who filed a class-action lawsuit against the NFL in 2012. Two years later he shared in a $765 million settlement.

That agreement placed a $3 million ceiling for those like McDonald who had dementia. But based on a formula that took into consideration his age and relatively late diagnosis, he received only $72,000.

“If he’d been diagnosed with CTE back then he would have gotten the full payout,” said his son. “But there was no way of determining that until after he passed. So you just kind of take it on the chin.”

It took this long after McDonald’s death to get a CTE confirmation, McKee said, because the brain first went to the University of Pennsylvania and because the number of players donating theirs to BU’s research program has exploded.

“We have more than 1,050 brains,” McKee said. “We get about 200 a year. It’s like a huge conveyor belt. We’ve had to ramp up the size of our team and we still have a delay of about eight to 10 months in getting these reports out.”

Despite exhibiting the disease’s symptoms for years, it wasn’t until his early 70s that McDonald finally received the dementia diagnosis, according to his son.

“He was old-school and wouldn’t see a doctor, but in the last 10 years of his life he really struggled,” Chris McDonald said. “He lost so much of everyday life. In public, he knew fans loved his liveliness, energy, and charisma. But at home he was very sedentary, didn’t do much of anything. He stopped going to his grandsons’ football games. He didn’t go to Hall of Fame ceremonies because he feared he was not going to remember who the other players were.”

The speedy wide receiver, one of the last in the NFL to perform without a face mask, played 12 years in the league.

“The severity of the CTE is significantly associated with the length of their football career and also their age,” McKee said. “We published a paper last year that showed for every 2.6 years of playing football the risk of developing CTE doubled. And for every 5.3 years, the risk of developing severe CTE doubled.”