(CNN)A pair of conjoined twin girls with an extremely rare condition have been successfully separated at a hospital in the Vatican City.
Ervina and Prefina, aged 2, were joined at the skull before an operation that lasted 18 hours and involved 30 doctors and nurses, according to a press release from the Bambino Gesù Pediatric Hospital published Tuesday.
The separation took place on June 5 and the girls, who are from the Central African Republic, are expected to make a full recovery.
The girls shared a skull and a majority of blood vessels.
This is the first time that doctors in Italy have successfully separated conjoined twins in total posterior craniopagus, which means they shared a skull and a majority of blood vessels.
There are no other cases of a successful intervention described in medical literature anywhere else in the world.