A team of surgeons in Dallas, Texas, have separated two-year-old twins from Egypt, who were joined at the head. The 26-hour operation appears to have gone well.

The delicate and difficult procedure to separate the twin brothers, who were joined at the head, began on Saturday, and ended 26 hours later at midday Sunday, Dallas time. Ahmed and Mohammed Ibrahim remain in a drug-induced coma, while plastic surgeons continue the work of reconstructing their skulls and closing the wounds at the top of each young patient's head.

Doctors say the operation was possible because the two brains were almost completely separate. But they say that cutting through the maze of blood vessels in their heads without causing permanent damage was a major challenge.

In a post-operation news conference at the Children's Medical Center, Neurosurgeon David Swift described the most difficult part of the surgery. "I thin the most difficult part was actually separating Mohammed's left hemisphere from the interface with Ahmed's right hemisphere. That was a bit of a surprise for us," he said.

Doctor Swift said that, if the two boys are awake and moving their arms and legs a week from now, it will be an indication that they have survived the procedure with minimal side effects.

The two boys had been joined at the head since they were born in a small village, 800 kilometers south of Cairo, on June second, 2001. Since June of last year, they have been living in Dallas, so doctors could study them closely.

The surgeons who worked on the effort to separate the twins donated their time, and the entire effort was sponsored by the Dallas-based Cranial-facial Foundation, a non-profit group that assists children with deformities of the head.