Auteur(s) : R. Hoffmann, Department of Dermatology, Philipp University, Deutschhausstraße 9, 35033 Marburg, Germany..
Illustrations
Figure 1. This is a stepwise
illustration of the complete TrichoScan procedure. A: a representative area
of the scalp is chosen and the plastic template is applied; B: all hairs
are carefully combed through the plastic template; C: the hairs are shaved
on the scalp surface; D: the shaved area is 1.8 cm2 in size;
E: 1 cm of dye is applied onto a wooden stick; F: 3 drops of developer are
mixed (G) with the dye; H: the dye is carefully applied onto the shaved
area; I: after 12 min the dye is carefully removed with an alcoholic solution;
J: digital images are taken at 20- and 40-fold magnification while the area
is still wet.
Figure 2. Example of the TrichoScan
analysis of hair number, hair density, cumulative hair thickness and anagen/telogen
ratio. The figure illustrates a digital image taken at 20-fold magnification
(left side of the image) and shows the area of 0.65 cm2 (blue
circle) which is analyzed with the TrichoScan software. The TrichoScan results
are illustrated on the right side, where the detected hairs are illustrated
with different colors. Red hairs are non-growing hairs (telogen), green
hairs are growing hairs (anagen) and yellow hairs touch the borders of the
circle. The right lower part of the figure shows a histogram of the different
hair lengths detected by the TrichoScan software.
Figures 3-6. The intra-class correlation of three different measurements
in 10 volunteers (subjects) from the same investigator is shown for hair
counts (Fig. 3) and for cumulative hair thickness (Fig. 4).
The intra-class correlation of one measurement in 5 volunteers (subjects)
from two different investigators is shown for hair counts (Fig. 5)
and for cumulative hair thickness (Fig. 6).
Figures 7 and 8. Hair counts
and cumulative hair thickness were analysed for 6 months in 11 volunteers
without AGA, in 5 untreated men with AGA, and in 12 men treated with finasteride
(1 mg/day). In controls and untreated men we noticed no significant difference
in the number of hairs within the observation time of 6 months (between
the values at baseline and after 6 months). In contrast those men treated
with finasteride showed a continuous increase (mean with 95% confidence
interval) at 3 months (p = 0.055) and at 6 months (p = 0.021) in the number
of hairs within the analysed area compared to the values at baseline. Untreated
men showed a continuous and significant decrease in the overall thickness
of hairs 3 and 6 months after the initial visit (baseline). In contrast
those men treated with finasteride showed, in comparison with the baseline
visit, a continuous and significant increase in the number of hairs within
the analysed area after 3 (p = 0.034) and 6 months (p = 0.006).
Figures 9 and 10. While defining
anagen hairs as growing and telogen hairs as non-growing hairs three days
after shaving, the TrichoScan is able to calculate a digital trichogram.
This figure illustrates the results (mean with 95% confidence interval)
from two investigators, who analysed of 18 volunteers with AGA the proportion
of anagen hairs (Fig. 9) and the hair growth rate (Fig. 10)
at the vertex and at the occiput (only 14 images). Compared to the occiput,
the AGA-affected scalp reveals a decreased number of and slower growing
anagen hairs. Both investigators produced similar results.
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