SINGAPORE -- Surgeons entered a critical phase Sunday in a dangerous, marathon operation as they began separating the brains of 29-year-old Iranian twin sisters joined at the head.\nThe operation, which could take two to four days, could be fatal to sisters Ladan and Laleh Bijani.\nLate Sunday, surgeons began separating the women's skulls and trying to replace a shared vein that drains blood from their brains. The process involves five neurosurgeons working simultaneously in front of and behind the twins, who are sitting in a custom-built brace, said a spokesman at Singapore's Raffles Hospital.\n"The next 12-24 hours will be a very critical period," Dr. Prem Kumar said. "That might be where we will have to traverse some possible difficulties."\nDoctors removed a vein from Ladan Bijani's thigh Sunday and will use that to compensate for diverting the shared vein to one sister's brain. Doctors have not yet determined which sister will keep the current vein and which will receive the graft.\nOther than sharing the vein, the women's brains are not joined -- though they touch inside their skulls.\n"I would say they are pretty much going according to plan and we are very pleased about the surgery," Kumar said summing up the surgeon's progress.\nAfter leading the incisions into the twins' skulls, plastic surgeon Dr. Walter Tan said, "Everything is going according to schedule."\nEarlier, doctors were upbeat about the surgery.\n"It's going to be a good day," the lead neurosurgeon, Dr. Keith Goh, said while arriving at the hospital. Goh and his wife spent the morning praying for the twins, he said.\nWhen asked to describe his mood, Dr. Benjamin Carson, the director of pediatric neurosurgery at Johns Hopkins Children's Center in Baltimore, said, "Sunshine."\nThe twins said they wanted to walk into the operating room as a sign of courage, but they were brought in by wheelchair because they were too tired to stand, Kumar said.\nAfter a lifetime of compromises on everything from when to wake up each day to what career to pursue, Ladan and Laleh said they preferred to face the dangers of the surgery rather than continue living joined together.
"If God wants us to live the rest of our lives as two separate, independent individuals, we will," Ladan said Saturday.\nAn international team of 28 doctors and about 100 medical assistants will participate in the surgery.\nThe Bijani sisters were born in Firouzabad, southern Iran, in 1974. Their heads are connected but their bodies are otherwise distinct.\nThis is the first time surgeons have tried to separate adult craniopagus twins -- siblings born joined at the head -- since the procedure was first performed successfully in 1952. The surgery until now has been performed only on infants, whose brains can more easily recover and adapt than adults.
