Follicular Map: A Novel Approach to Quantitative Trichoscopy

Background: Trichoscopy (hair and scalp dermoscopy) is gaining importance as an easy-to-use diagnostic and monitoring tool in various hair and scalp conditions. Objective: The demand for a method to identify exactly the same site on scalp skin for subsequent examinations is growing constantly. Methods: In total, 40,000 trichoscopic images of 70-fold magnification were analyzed. Graphical pattern recognition was used to identify hair shafts in trichoscopy images and to derive the coordinates of all follicular orifices. Determination of the relative positions of hair follicle orifices formed the Follicular Map (FMap). Processing and matching of FMaps involves conceptually simple but computationally complex numerical algorithms. Results: FMaps were shown to be unique for specific locations on the scalp in each human individual. The follicular patterns were not affected by natural hair cycling processes and remained unchanged over the course of time. It has been tentatively verified that FMaps remain unaffected by noncicatricial alopecia. Conclusions: The concept of FMap presents a novel approach to qualitative trichoscopy, allowing precise evaluation of treatment efficiency, clinical trial quality control, validation of diagnostic tools, and potentially other applications still to be discovered. The FMap enables the location of hair follicles to be precisely measured and recorded. (c) 2019 S. Karger AG, Basel