fig10

Figure 10. Ultrasound study of follicular implantation. For clinical illustration, two hair fibers were gently pulled to elevate the skin-hair junction at the exit point. The region of interest was then marked with three green dots, and the margins of the circular probe were outlined with 13 green dots. These steps help position the ultrasound probe to focus on the opening of the grafted hair follicle to be scanned (indicated by red and blue lines). Once in place, the scanning allows beamer steps in the order of 100 µm shifts. In A1, the blue arrow points to the opening of the grafted hair follicle, where the hair shaft exits at the skin surface. The red line indicates the path of the scanning beam, and the resulting ultrasound image is shown in panel A2. The image clearly shows the epidermis as continuous (blue arrow with an arrowhead on the white spot in the upper right corner of panel A2), with a slight epidermal bump and a hypo-echogenic field beneath. In panel b1, the blue line illustrates the axis of a shifted beam (at a 200 µm distance to the right side of the red axis shown in A1). The corresponding ultrasound image (B2) clearly shows a disruption in the epidermis (blue arrow with an arrowhead on the white spot in the upper right corner of B2). The follicle remains in continuity with the hypo-echogenic zone underneath, at an estimated average depth of 250 µm beneath the epidermal surface, while the fiber inside the follicle appears echogenic. The skin below the arrow shows a hypo-echogenic dermis, which may partly, though not exclusively, indicate superficial dermal atrophy due to aging (or photo-aging, although the volar aspect of the forearm was less sun-exposed).