Until his breakthrough the procedure, a hemispherectomy, was risky and unpopular with specialists, given the often tragic outcomes. Dr Carson believed the child's brain was still undeveloped and could recover from the radical approach, unlike hard-wired adult brains.
In 1985 he operated on a 4-year-old girl called Maranda, broken from as many as 100 seizures a day. Dr Carson told her desperate parents that he had never performed the dangerous surgery and could not guarantee the outcome.
As things stood, Maranda didn't have a life, her parents said, and faced paralysis, mental decay and death. She survived the 10-hour operation and got a life she might never have imagined, even learning to tapdance.
Interviewed by telephone from the United States, Dr Carson says he most delights in the reactions of parents to news that surgery has worked.
"It's wonderful when you go out to that waiting room and say to the parents, 'Your child is awake and asking for you.' Nothing really beats that."
A year later Dr Carson operated on an unborn baby. The child, a twin, had hydrocephalus, where fluid was gathering on its brain. The then-radical operation tested the limits of technology and medical knowledge. Once again the surgery succeeded, though the relatively young specialist came under fire from conservative senior colleagues.
Within a year the public and professional glare intensified when Dr Carson and a team at Johns Hopkins Hospital in Baltimore separated twins joined at the back of the head - "craniopagus" twins.
Months in preparation, the intricate surgery on the Binder brothers took 22 hours and pushed medicine into uncharted territory.
Seventy doctors working in teams tackled the impossible, inducing hypothermia in the 7-month-old German boys and stopping their hearts for an hour while a mass of veins around their brains was untangled. The infants were effectively in suspended animation until an electric jolt kick-started their hearts. The boys - Patrick and Benjamin - survived with disabilities and their personal circumstances soured. Dr Carson said the Binder parents separated, and the twins became wards of the state: "I kind of lost track of them."
He has a happier account of craniopagus twins he helped separate in 1997 in South Africa. Leaps in medical technology meant doctors who worked on the 28-hour operation had repeatedly done a "virtual" operation before separating the little boys. Joseph and Luka Banda made a complete recovery.
In the United States Dr Carson is a celebrated surgeon, though he resists the idea of being a celebrity doctor. He has written three bestselling books about his life and philosophy and, yes, there's a film - starring Cuba Gooding jnr - which chronicles his journey from bottom of the class to top of the surgical tree.
Raised by an illiterate solo mother - who was one of 24 siblings - he grew up in a poor Detroit suburb. Glasses helped overcome early reading problems, before his mother, Sonya Carson, decided her sons were wasting their lives watching television.
She rationed their viewing and challenged them to read and write weekly reports on the titles she made them devour. Slowly, and somewhat reluctantly, the boys entered a world of books, their inquisitive young minds soaking up knowledge.
Even then Ben Carson nearly didn't make it. As an angry teenager, goaded by classmates over a trivial dispute, he thrust a knife into the belly of a friend. But rather than slicing into flesh, the blade struck his rival's belt buckle and broke. A centimetre or two and the 14- year-old's future could have been bleak.
He was struggling at school, but the fateful break seemed to snap something in him.
"When I think back," reflects Dr Carson, "that was something that helped me realise how much potential is out there in young people that is simply wasted if not developed."
In March Dr Carson is to bring his feelgood story and his advocacy to New Zealand. A fervent campaigner for literacy and lifetime learning, and a devout Christian, he is the guest speaker at a joint fundraiser for Starship Foundation and the Duffy Books in Homes programme. Organisers have invited 7000 children to the Telstra Clear Pacific Events Centre to hear a few life-lessons.
With his wife, Candy, Dr Carson has created some paths designed to put young Americans on the pedestals claimed by movie stars or sporting heroes. He set up a fund to support talented students, partly to encourage the idea that academic achievement is as admirable as superstardom, and is behind another fund that helps pay the costs of uninsured patients with complex medical needs.
Dr Carson, awarded the Presidential Medal of Freedom by President George W. Bush - the highest US civilian honour - is in heavy demand as an inspirational speaker.
Asked what he tells youngsters, he said: "What I try to get kids to realise is the person who has the most to do with what happens to you in life is you. It's not somebody else. It's not the environment - it's the choices you make and the energy you decide to put behind it.
"I tell young people that the average person lives to be 80. You can spend the first 20 to 25 years preparing yourself. If you do you reap the benefits - if you don't, then you suffer the consequences."
Be inspired
Tickets for the fundraising dinner on Tuesday, March 6 can be bought at www.starship.org.nz/drbencarson, by calling 0800 383 392 or emailing drbenvisit@booksinhomes.org.nz
