Background: Occipital scars from donor strip harvesting during hair transplantation are an important cosmetic concern. Scalp laxity has an important role, due to the more frequent use of dense packing and megasession transplantation, which requires more grafts and creates a wider, longer donor scar.
Objective: To determine if the use of a simple, objective measurement of occipital scalp laxity could reduce scar length by allowing for adjustment of donor strip harvesting during hair transplantation.
Methods and materials: This retrospective study included data from 39 patients who underwent hair transplantation with >2000 follicular units: 25 patients underwent measurement of occipital scalp laxity (measurement group); the other 14 did not (control group). We measured and calculated preoperative scalp parameters for hair transplantation, including follicular unit density at occipital scalp, length and width of the donor strip, and estimated total number of grafts. All patients underwent standard follicular-unit hair transplantation, at which time the actual total number of grafts was determined.
Results: Mean occipital follicular unit density in the measurement group was 74.16 follicles per cm2, which did not significantly differ from the controls (73.29; t=0.410, d.f.=37, P>0.05). The mean length of the occipital surgical wound was significantly shorter in the measurement group than in the controls (19.16 vs 27.50 cm, respectively; t=10.412, d.f.=37, P<0.05). The difference between the estimated and actual total number of grafts was significant in the measurement group (2139.44 vs 2397.64, respectively; paired t=3.095, d.f.=48, P<0.05) but not in the control group (2277.71 vs 2296.71, respectively; paired t=0.175, d.f.=26, P>0.05). Accuracy in estimating the total number of grafts was poor for the measurement group, as the number of actual grafts significantly exceeded estimates.
Conclusion: Use of data from a simple, objective method to measure occipital scalp laxity simplified adjustment of strip harvesting, allowed for use of wider strips, and resulted in smaller donor wounds and scars from hair transplantation; however, accuracy in estimating the total number of grafts was reduced.