Surgeons take 27 hours to separate the two baby boys who were conjoined at the tops of their heads, sharing blood vessels and brain tissue.
Surgeons at a New York City hospital on Friday 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.
Twin boys Jadon and Anias McDonald were successfully separated after 27 hours of surgery, doctors at Montefiore Medical Center in the Bronx announced said.
The thirteen-month-old twins shared blood vessels and brain tissue, an extremely rare condition that occurs once in every 10 million births.
The separation itself took 16 hours and continued in order to rebuild their skulls and make them whole. While the twins survived the surgery, the outlook for their health is unclear.
A hospital spokesman said that the surgery "required a team of 40 Montefiore experts in the fields of nursing, anesthesiology, neuroradiology, neurosurgery, and plastic surgery".
Their mother, Nicole McDonald, posted about the surgery on Facebook and said that even though she was very cautious about the future, she was very thankful.
The McDonalds raised more than $100,000 to separate and care for the boys.
Led by pediatric neurosurgeon Dr. James Goodrich, the operation, known as a craniopagus surgery, was only the 59th such surgery ever to take place since 1952, the hospital said.
Separation is crucial – about 80% of cranially conjoined twins die by the time they reach their second year of life.
In 2004, Goodrich separated cranially conjoined twins Carl and Clarence Aguirre of the Philippines, who are now teenagers. Those twins still undergo physical therapy and Carl has limited use of his left arm and leg.
The recovery process for the McDonald twins is likely to be very long as well.
"We are standing on the brink of a vast unknown," McDonald said in a separate Facebook post. "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," McDonald said.
During the operation, surgeons found a five-by-seven centimeter 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," 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 Center.
Success rates in surgical separation are similarly dismal and depend on the point of connection.
For instance, the medical center says, 68% 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.