Q: I am interested in FUT. How do you figure out how large a strip to use for the hair restoration when transplanting all follicular units? — P.K., New York City, N.Y.

A: The length of the donor strip incision is determined by the number of follicular unit grafts required for the hair restoration.

There are slightly less than 100 follicular units/cm2, so if a 1cm wide strip is used, a hair restoration procedure requiring 1800 grafts would need a strip that measured slightly more than 18cm in length.