Twin girls conjoined at the head successfully separated by 30-strong surgical team

It took 11 hours to separate the ten-month old girls, conjoined in the rarest possible way

Twins Erin and Abby Delaney at the Children's Hospital of Philadelphia in September 2016 (AP)

Twin girls conjoined at the head have been successfully separated by a 30-strong team at a children’s hospital in Pennsylvania.

Erin and Abby Delaney’s shared blood vessels and the protective membrane around their brains had to be carefully teased apart during the 11-hour surgery.

The surgeons then split into two groups to perform reconstruction on each girl.

Surgery equipment such as monitors and tape was marked with green or purple tape to differentiate each girl.

The 10-month-old twins from North Carolina are currently recovering in intensive care, and have been placed in separate beds for the first time in their lives.

They were delivered prematurely by Caesarean section last July.

Their parents sought specialist pre-natal care after they found out they were expecting conjoined twins 11 weeks into mother Heather’s pregnancy.

The Children’s Hospital of Philadelphia said its surgeons had separated conjoined twins 23 times over the past 60 years, but this was the first time children joined by the top of their heads had been involved.

The condition, called craniopagus, is the least common type of conjoining.

Parents Heather and Riley Delaney are planning a big coming hope party for their baby twins (AP)

The team performing the separation surgery on June 7 included physicians, nurses and specialists in neurosurgery, plastic and reconstructive surgery, and anesthesiology.

"Separating conjoined twins is a very complex surgery followed by a long and complicated recovery, but we are very hopeful for a positive outcome," said Dr Jesse Taylor, the plastic surgeon who helped lead the team.