Neurosurgeons performing a dangerous, marathon operation to separate Iranian sisters joined at the head grappled yesterday with rerouting a shared vein as thick as a finger that helps blood flow through the twins' brains.
An international team of five neurosurgeons probed the brains of 29-year-old Ladan and Laleh Bijani as a crucial phase began in an unprecedented operation expected to last two to four days, a spokesman for Singapore's Raffles Hospital said.
"We are not done with the critical phase. There may still be some difficulties encountered, but up until now we are quite satisfied with the progress of the whole surgery," Dr. Prem Kumar said.
"Up until now, the twins have taken to the procedure quite well," he said. "They are stable, the anesthesia is working quite well, so we are cautiously optimistic."
The operation could kill one or both of the sisters, but after a lifetime of compromising on everything from when to wake up to what career to pursue, the Bijani sisters said they would rather face those dangers than continue living joined.
Before dawn, surgeons began stitching a vein taken from Ladan's thigh to one of the twin's brains to compensate for the removal of the shared vein, Kumar said. He would not say who received the finger-thick vein.
The shared vein is the biggest obstacle in the surgery: Other than sharing the vein, the women's brains are not joined -- although they touch inside their skulls. Their bodies are otherwise distinct.
German doctors told the twins in 1996 that the shared vein, which drains blood from their brains, made surgery too dangerous.
Classical music played softly as three surgeons worked simultaneously in tight spaces in front of and behind the twins, who are sitting in a custom-built brace connected to an array of lines feeding them intravenously and monitoring their vital signs, Kumar said.
"Nothing is going on at a hurried pace," he said. "Everything is quite calm and measured. There's lots of discussion."
Surgeons expected to begin separating the twins' brains yesterday afternoon after encountering unexpected delays cutting through their skulls when the bone turned out to be denser than previously thought, Kumar said.
"The procedure took six hours -- longer than originally expected -- because the bones were thick and compact, especially in the areas where the two skull bones fuse," Kumar said.