NEW : They implanted a piece of synthetic bone and also a shunt in U.S. Senator Gabrielle Giffords ' brain . NEW : The procedure drains excess fluid from her brain . She was shot in January in Phoenix , Arizona . Doctors called her progress ' almost miraculous '
NEW : Surgeons implanted a piece of synthetic bone and also a shunt in U.S. Rep. Gabrielle Giffords ' skull . NEW : The shunt drains excess fluid from her brain . Giffords was shot in January in Tucson , Arizona . Doctors call her progress 'almost miraculous '