Weathering of the Hairless Scalp: A Study Using Skin Capacitance Imaging and Ultraviolet Light-Enhanced Visualization

In a study conducted on 50 men aged 46-63 years with phototype III skin, researchers used skin capacitance imaging (SCI) and ultraviolet light-enhanced visualization (ULEV) to examine the weathering of the hairless scalp. The ULEV method revealed discrete melanoderma presenting as speckled darker perifollicular dots and larger globular interfollicular macules, which were not well captured by regular color photography. The hairless follicles were filled with whitish or dark keratotic plugs of relatively uniform size, and the severity of the faint melanoderma was unrelated to the density and size of these plugs. SCI showed a pattern of small whitish dots surrounded by a darker network, with larger whitish areas corresponding to the follicular keratotic plugs and their surrounding scaly rim. The study concluded that chronic solar ultraviolet light irradiation has little or no effect on the follicular plugs and that the appearance of the hairless scalp is different from other body parts, with no clinically relevant criteria for stratifying subjects into well-defined subgroups. The findings suggest a peculiar intercorneocyte adhesion pattern centered around hair follicles.