DALLAS, Oct 12: Doctors separated two-year-old Egyptian twins joined at the crown of their heads on Sunday, giving them independent lives in a medical procedure that, so far, has had no complications.

Eighteen doctors working in shifts have been operating on Ahmed and Mohamed Ibrahim at Children’s Medical Center of Dallas. They were separated about 27 hours after the surgery started and doctors were working to reconstruct their skulls and close their wounds, the hospital said in a statement.

After more than a day of surgery, doctors completed the most difficult and dangerous part of the procedure — separating the shared brain material and the shared circulatory systems that feed bloods to their brains.

Dr. Jim Thomas, the chief of critical care at the hospital, told a news conference the medical procedure was in the “home stretch.” If there were no major complications, the operation should end on Sunday, he said.

He said during surgery the boys had not suffered major blood loss, had had no pulmonary problems and no significant or unexpected swelling in either of their brains.

“Things have gone according to surgical plans. There have been no surprises, and none of the potential complications that surgeons have prepared for have occurred,” he said.

The surgery in Dallas was the first such procedure since twin Iranian women joined at the head died in July at a Singapore hospital.

Doctors said if the boys were not separated, they would likely never be able to walk without help and face a lifetime of medical complications.

A team of cranial and facial surgeons is repairing the damage to their skulls, using tissue from an area around their thighs that had been expanded — using balloon-like devices — months before surgery.

Thomas said the boys were not out of the woods yet and even with a successful separation, they still faced years of reconstructive surgery to repair the places where their skulls had been fused together.

Two teams of medical ethicists reviewed the boys’ case before surgery and concluded that the prospects for a successful separation offered benefits that outweighed the certain and progressive loss of functions the twins would face if they remained conjoined.

The boys cannot stand on their own because of the way their bodies are joined. They are more than 6 feet (1.8 metres) long from the toes of one twin to the toes of the other.

In the first phase of the operation, doctors removed balloon-like devices designed to expand the areas of the boys’ heads where they will be separated. Five neurosurgeons then separated some brain matter the boys shared and divided the shared circulatory system to their brains.

The boys have been in Dallas for more than a year and undergone intensive diagnostic testing and planning for the surgery.

Ahmed and Mohamed were born in a small town 800 kilometres south of Cairo on June 2, 2001, and have been under medical care almost all of their lives. The two boys are healthy, alert, playful, and are starting to learn a few words.

Iranian twins Laleh and Ladan Bijani, 29, died on July 8 from blood loss after a 52-hour operation by 28 specialists at Singapore’s Raffles Hospital.

Conjoined twins at the head account for about one of every 2.5 million births and about 2 percent of all conjoined births.—Reuters