DHI method can be seen with different names such as Implanter Pen or CHOI hair transplant. It was first developed in Korea National University. As it can also be understood from its name, direct hair implantation consists of implanting the extracted grafts directly into the recipient area without pre-made incisions (canals). Even though some clinics show it as a different technique from FUE, it is not. Because FUE is an extraction method and it is also used in a DHI hair transplantation to extract the grafts. It only changes the way of implantation by using implanter/CHOI pens.