| Some practitioners excise a relatively
wide donor strip that extends through the left and right occipital and parietal
areas but avoids the region superior to the auricles. The primary advantages of
such a harvest are an increased hair yield and a higher proportion of pigmented
hairs. If your patient prefers a short hairstyle in the temporal areas, this may
also be the most appropriate pattern, in order to conceal the donor scar.
However, while FUD and hair density are greatest in the mid-occipital region and
superior to the mastoids, decreasing superior to the auricles, the highest
preponderance of natural single hairs is superior to the auricles. (Table 8.)
This midline excision pattern is also potentially the most inefficient means
of donor harvesting when multiple procedures are carried out. Scars inevitably
decrease the ultimate donor yield, and this technique has the greatest potential
for the most and/or widest scars, because the length of the strips is shorter
than those that extend into the temporal areas. Therefore the width or number of
excisions must be increased to produce the same number of hairs. In addition,
the tapered ends of the donor strip(s) often contain the most follicular
trans-section and this occurs in an area with high FUD and hair density if the
donor strip stops before entering the less dense supra-auricular regions.
Furthermore, the "virgin" supra-auricular area has a far lower hair yield
capacity when treated as a separate entity, as its length relative to the length
of its tapered ends, is less advantageous.
This pattern also fails to take advantage of the temporal hairs’ natural
tendency to lose pigmentation first. As noted earlier, hairs chronologically
programmed to maintain pigmentation longer may, in later life, lead to a
cosmetically noticeable disparity between the hair color of the grafted region
and the adjacent temporal areas, which have a more "salt and pepper" appearance.
It has been noted that non-pigmented hair is much more difficult to dissect into
FU. Even with microscopes it can be very difficult to maintain a high hair yield
from non-pigmented donor regions. Therefore, a harvest limited to occipital and
parietal areas has the capacity to improve FU yield if one is operating on
someone whose temporal hair is already less pigmented. As has already been
noted, in such cases, obtaining grafts that contain more than one FU may be
advantageous.
HARVESTING CURLY HAIRMarkedly curled hair, such as Negroid hair,
presents a different problem. (See also Chapter 15). The incision must follow
the curvature of the hair shaft to avoid its trans-section. Arnold has described
a technique of incising the donor area with a hand-made curved scalpel blade.
Cole prefers Arnold’s technique with the Negroid hair. The resulting strip may
also be "pre-slivered" in the donor area with incisions made perpendicular to
the long axis of the strip as described earlier in this chapter and by
Blugerman, Alkek, Al Ghamdi, and Kohn.** Unfortunately, in these authors’
admittedly limited experiences, this latter type of dissection is likely to
produce more trans-section than if there is direct visualization of the donor
tissue during its dissection into grafts.
Using a multi-bladed knife in individuals with tightly curled hair will
almost certainly result in a higher follicle trans-section rate than if a single
strip or elliptical harvest is employed, and a multi-bladed knife is therefore
contraindicated. On the other hand, harvesting of Negroid hair is one of the few
times when the use of the "old" power punch may be advantageous. Power punches
can be moved in a gentle arc that follows the curvature of the follicle as the
individual grafts are being drilled out. Round grafts that are 4 to 5 mm in
diameter can be removed and divided into whatever size grafts are required. Cole
also sometimes uses a power punch at the end of a case of FUT in which 20 or
more empty FU size recipient sites remain after all the FU have been used. He is
better able to get control close to the number of FU he wants by calculating how
many of these grafts will be necessary to produce them.
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