Careful manipulation of hair grafts is essential for a good yield of transplanted hair.

The aim of this study was to evaluate some of the factors responsible for poor graft yield, such as dehydration of the graft and the temperature and duration of preservation.

First, for the dehydration study, isolated single hair follicles were left on dry gauze for 0, 5, 10, 20, and 30 minutes at room temperature. Secondly, to evaluate the effect of preservation temperature and time on the hair graft, follicles were preserved in saline for 5 minutes as a control, then for 6, 24, and 48 hours both at room temperature and at 4℃, respectively. Viability of preserved follicles was judged based on organ culture.

Elongation of hair folliciles was seen in 96%, 94%, 94%, 83%, and 68% for 0-, 5-, 10-, 20-, and 30-minute air-exposed groups, respectively. Survival was seen in 95%, 92%, 40% and 34% at room temperature and 96%, 94%, 76% and 50% at 4℃ for follicles preserved in saline for 5 min (control), then for 6, 24, and 48 hours, respectively.

We suggest that, alone with careful manipulation of hair units, high survival can be achieved with the avoidance of graft dehydration and preservation of the grafts at low temperatures if the operation time extends for more than 6 hours.