Surgery is required to treat this growth. Even after surgery, it can grow back. When the doctor removes only the growth and leaves the spot underneath exposed, the growth returns in about 80% of patients. A new surgery technique removes the growth and then covers the spot with tissue. This surgery is called a tissue graft. When a tissue graft is used to cover the bare spot, the pterygium does not regrow in as many eyes as when the spot is left bare.