Dr. Donald Nuss, based at Children's Hospital of The King's Daughters in Norfolk, Virginia, performed the first minimally invasive repair of pectus excavatum (MIRPE) in 1987[33] and presented it much later at a conference in 1997.[33][34][35] His procedure, widely known as the Nuss procedure, involves slipping in one or more concave steel bars into the chest, underneath the sternum. The bar is flipped to a convex position so as to push outward on the sternum, correcting the deformity. The bar usually stays in the body for about two years, although many surgeons are now moving toward leaving them in for up to five years.