Surgeons at a New York City hospital have separated a pair of 13-month-old boys who were congenitally joined at the head, completing a rare operation that carried a risk of death and severe brain damage, their mother said.
Jadon and Anias McDonald of Coal City, Illinois, underwent 16 hours of surgery at the Children's Hospital at Montefiore Medical Center in the Bronx before the surgical team, led by Dr James Goodrich, fully detached their skull and brain tissue, Nicole McDonald wrote on Facebook.
"Finally reunited. How surreal," Mrs McDonald wrote.
"I now realise that I always saw you as separate because seeing you like this is really nothing different to me. When I stand at your bedside, Jadon, it's almost as if Anias is still there. Anias, when I leaned over you I protected my hair from Jadon. But the view is still the same. This is how I always saw you. I love you so much."
"Now it's time to step forward into the new chapter of our life. I'm ready to fight and I know you are too."
While the twins survived the surgery, the outlook for their health is unclear.
"We are standing on the brink of a vast unknown," Mrs McDonald wrote.
"The next few months will be critical in terms of recovery and we will not know for sure how Anias and Jadon are recovering for many weeks."
High-tech modeling was used to help the surgeons separate the brothers, but the vasculature involved in the procedure was more complex than the images showed, Mrs McDonald said.
During the operation, surgeons found a five-by-seven centimetre area of brain tissue with no clear line of dissection.
"Dr Goodrich had to make the call and the final cut based on his instinct," Mrs McDonald said.
Anias, who remained in surgery longer than Jadon, appeared to suffer more than his brother by the separation of the brain tissue.
The boy, whose heart rate and blood pressure dropped during the operation, is being monitored for brain swelling and stroke, McDonald said. He is expected to suffer some type of paralysis during his recovery.
Jadon "hardly batted an eye through the whole procedure in terms of maintaining his vitals," McDonald said.
The twins, who also underwent skull reconstruction on Friday, will be intubated for about a week while their brains and vital signs are monitored.
About one in 200,000 births produce conjoined twins, with about half arriving stillborn and about a third surviving a single day, according to the University of Maryland Medical Centre.
Success rates in surgical separation are similarly dismal and depend on the point of connection.
For instance, the medical centre says, 68 percent of twins joined at the base of the spine have been successfully separated while there have been no known separation survivors of twins connected at the heart.
"We just took a huge leap of faith," McDonald said. "I'm still frozen in space and time ... I'll be hanging out there until I see those smiles again."