In autologous tissue reconstruction, either a free or a 'pedicled' (or 'mobilised') flap can be used. Free flap reconstruction usually involves removing skin, fat and sometimes muscle from the lower abdomen or buttock, and grafting it to the breast area, using microsurgery to establish a new blood supply. Pedicled flap reconstruction usually involves tunnelling of skin, muscle and fat from the back or abdomen through to the chest, with the tissue flap remaining connected to its original blood supply. If there is not enough tissue to create a whole breast, an implant may also be used. Although pedicled and free flaps are conventionally harvested by open surgery, endoscopic techniques have recently been developed with the aim of speeding recovery and minimising scarring caused by skin incisions.