“…These data can contribute to preoperative evaluation, surgery planning, and postoperative outcome evaluation performed by hair transplantation surgeons. The required amount of hair transplantation, area of donor site excision or extraction, postoperative density, and cost may be estimated, depending on the area of recipient site during the preoperative consultation [11,12] . For example in a male patient with vertex hair loss with a recipient site measuring 2 cm × 2 cm, assuming that all the transplanted FUs survive, the transplantation of 200 FUs can achieve 60% of the normal density of vertex hair.…”