The state of the art. Donor site harvest, graft yield estimation, and recipient site preparation for follicular-unit hair transplantation.

The field of hair transplantation has moved beyond the provision of a dense frontal hairline to techniques that are designed to provide a natural appearance in as few sessions as possible. The concept of the follicular unit has revolutionized the preparation of both the grafts and the recipient sites. We will describe the mathematics of hair restoration and our techniques for determining the length and height of the donor strip for a given number of desired follicular-unit grafts. We will also elucidate our technique for cutting the follicular-unit grafts using microscopes and transillumination. We now use specially designed blades or punches to make shallow slits or slots for recipient sites. Striving for teamwork and efficiency is of paramount importance in hair transplantation, and we will describe our coordination and training methods as well as the role of the surgeon.