Follicular bisection in hair transplantation surgery

The aim of this study was to evaluate, in an in vitro model, the survival and growth rates of transversely sectioned human hair follicles to assess experimentally the soundness of this approach as a future possible method for "duplicating" available donor hair grafts in hair transplantation procedures. Furthermore, we have grafted bisected hair follicles in 11 inbred mice, in order to in vivo evaluate the soundness of this procedure. A total of 300 human anagen hair follicles were thus randomly assigned to one of the following groups: group A, cultured intact as dissected, and group B, transversely transected. Regarding the in vivo animal model, we have prepared 96 emimicrografts transplanted in the dorsum of the inbred mice. No statistically significant differences were found between the growth rate of intact follicles and of lower-half follicles, whereas a statistically significant difference was found between the growth rate of follicles from the two above mentioned groups and the growth rate of the "upper-half" follicles. In our opinion, the reported in vitro and in vivo survival rates of transected human hair follicles represent an interesting starting point in striving to augment the number of donor hairs available during a hair transplantation procedure.