Immediate-Onset Linear Effluvium Associated With High-Density Hair Transplantation: A Series of 28 Cases.

We describe 28 patients who experienced effluvium with previously unreported features shortly after hair transplant surgery. Notable features were as follows: a) a linear morphology; b) immediate onset (1-3 days); c) association with dense-pack grafting in areas of receding hairline at the temples (Mickey Mouse pattern); d) a progressive increase in the diameter of the hair loss line (wave-like pattern); e) in some cases, subsequent concentric linear effluvium on the crown (donut pattern); and f) other forms of previously unreported immediate-onset effluvium. The linear morphology could be the result of dense packing, which can cause perilesional hypoxia and loss of miniaturized hairs around the recipient area. Since linear hair loss can cause patient concern about graft failure, we recommend taking images of transplanted and nontransplanted areas immediately after surgery and warning patients in advance about these transient effects, which are fully reversed in 3 months.