In a historic operation of conjoined twins in the world, neurosurgeons working in a life-threatening surgery to separate Iranian twin sisters, Ladan and Laleh Bijani, 29, joined at the head, cut through brain tissue a millimetre at a time Monday. Dr Prem Kumar Nair, a spokesman for the Raffles Hospital here, where the twins are undergoing the surgery, said although the brains of Ladan and Laleh are separate, ‘‘they are very adherent to each other’’. The medical team also discovered during the operation that the pressure in the twins’ brains and circulatory system was unstable. The widely-publicised operation, which began about 10 p.m. EDT Saturday, could take up to four days. The Iranian government said Monday it would pay the nearly $300,000 cost of the surgery. Earlier, Raffles Hospital offered to underwrite the cost of the operation and doctors offered to waive their fees. Five neurosurgeons completed one of the most dangerous steps by rerouting the shared vein, which is as thick as a finger, and successfully attaching a vein graft. The women’s brains touch inside their skulls. The sisters’ bodies are otherwise distinct. Rerouting the shared vein was considered the biggest obstacle in the surgery. German doctors told the twins in 1996 that the vein made surgery too dangerous. ‘‘There may still be some difficulties,’’ Nair said. 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 it. This is the first time surgeons have tried to separate adult craniopagus twins. The surgery has only been performed successfully since 1952 on infants. The Bijani sisters were born in Firouzabad in southern Iran in 1974. President Mohammad Khatami has hoped for the operation’s success.
