A second World War veteran who was blinded in his right eye when he was hit by shrapnel can see again after being head-butted by a pedigree racehorse.

Doctors tried in vain for 64 years to restore Don Karkos's sight, until My Buddy Chimo stepped in.

Hours after the horse smacked the 82-year-old paddock security guard in exactly the same spot as the shrapnel gashed his forehead in combat in 1942, he realised his vision was returning.

"I was putting a collar around his chest, and he whacked me real hard with his head," Mr Karkos told the New York Daily News.

"Being kicked is part of the job, but I've never been hit that hard.

"I was pretty shaken up, kind of dazed. Then, later that night, I started to get the vision back in my right eye.

"It was unbelievable. I've been seeing doctors all my life, and they've always told me there is nothing can be done."

Although his vision is still not perfect, Mr Karkos has been able to see about 15ft with his damaged eye since the incident at the Monticello Raceway racecourse in New York state two months ago.

"What happened is still a mystery to me," he said.

"But I do know I had got used to not seeing things and bumping into walls, and I don't do that anymore."

Dr Douglas Lozzaro, the head of ophthalmology at Long Island College Hospital, said the blow could have knocked a dislocated lens into place.

Mr Karkos said he was eager to show his gratitude to My Buddy Chimo.

"I'm on very good terms with that horse now, and he gets special care from me," he said.