Perception of Baldness and Hair Density

Publisher Website
Google Scholar
Abstract
Background: Androgenetic alopecia needs to be scored precisely. Objective: A possible measure is the ratio between the hair density in the parietal area and that in the occipital area which, being not affected by baldness, supposedly has a ‘normal’ density. Methods: On the vertex and just below the occipital protuberance of 109 men, two 1-cm2 areas were identified. In both areas, hairs were clipped short and photographed by a videomicroscope. Hairs were then counted within a 30-mm2-wide central square section. Results: In the occipital area, the average count was 127/cm2, without differences among the Hamilton/Norwood classes. In the parietal area, the average density significantly diminished from 138 to 47/cm2. A main difference was found between classes 1–3 vertex and classes 4–6. Conclusions: The parietal/occipital ratio decreased significantly only when baldness was clinically manifest. The parietal/occipital ratio cannot be a better measure of baldness severity than the rough Hamilton/Norwood scale. The perception of early baldness does not depend on the diminished hair density, but also on the progressive thinning of the hair shafts.