A corneal transplant involves replacing either a portion of the cornea or of the entire central cornea with corneal donor tissue. As it is a more invasive surgery, its complications can be much more severe. It typically requires a long recovery period of several months to a year. The Intacs procedure does not require removal of corneal tissue, but rather reshapes the weakened cornea by adding mechanical support to it. The recovery period is typically shorter, with more rapid improvement in vision. The synthetic material of Intacs is not at risk for rejection the way donor transplant tissue is. In some cases, if Intacs are not effective, patients can proceed with corneal transplantation.