Digital Imaging for Measuring of Hair Growth on the Human Scalp
Any analysis method for hair should be able to reliably analyze the most important biological parameters of hair growth, such as hair density (1/cm2), hair diameter (μm), hair growth rate (mm/day), or anagen/telogen ratio, just to mention a few. In addition, any technique must produce results which are representative for the whole scalp. The basic principle of digital phototrichogram imaging is the same irregardless of the system used: The growth of hairs in a defined target area is measured by analysis of images following close clipping of hairs to the scalp. Repeated imaging of the same target area over time allows assessment of the efficacy of hair-promoting drugs or products. Differences between analysis systems can be found in the parameters which can be measured and, importantly, in the methods used to mark the hairs in images prior to analysis. Herewith we provide insight into the theoretical and statistical background of hair analysis and the sensitivity of the method with reference to recent clinical trial data obtained using the TrichoScan® system.
KeywordsTarget Area Hair Loss Vehicle Group Hair Growth Hair Density
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