Working from the inferior aspect toward the superior aspect has certain advantages. (a) As noted earlier, hair-angle on the inferior side of the scar is distorted to a variable degree, while that superior to the scar maintains a more natural angle. There is, therefore, less risk of follicle trans-section when a strip is removed from the superior side of the scar. (b) Working from inferior toward superior may also improve the patient’s ability to conceal the scar. Should MPB progress inferiorly with the passage of time, there is less likelihood that it will impair camouflage of the donor site scar or advance into previously harvested areas. (c) Going from inferior to superior, results in the mobile neck-skin being pulled progressively into the donor region, rather than the alopecic or future alopecic crown being pulled into the donor region, if one instead harvests from superior to inferior - thereby, possibly enlarging the alopecic crown. On the other hand, superior donor strips can be considerably longer than the most inferior ones, enabling the production of more grafts than the latter. Superior strips can also be wider and result in lower wound tension, as Seery pointed out earlier in this chapter. Of course lower incisions can be angled superiorly rather than stopping posterior to the auricles. In this instance, the inferior incision might be longer.

Harvests extending from supra-auricular region to supra-auricular region require a turn over the occipital protuberance. This is not problematic with a single blade. When more than one blade is used the inferior blade must travel faster than the superior blade at this turn. For this reason Cole terms this movement the critical turn of the occipital protuberance. This turn is similar to running around a track 440 meters long. As the racer approaches each turn, the outside lane has a greater distance to travel around the turn. Therefore, he must run faster or be given a head start so that all runners race equal distances. The speed of the inferior blades must increase as the distance between the blades increases. It is almost impossible for three or more blades to each engage this turn at their respective ideal speeds. Hence, the risk of follicle damage is greater at the critical turn and increases significantly as the number of blades increases.

Harvests beginning in the middle of the donor area offer an important advantage that the other two options don’t: Hair becomes progressively finer and sparser in the most inferior and superior aspects of the donor area, as the patient ages. Every effort should, of course, be made to not harvest from areas in which future thinning can be anticipated to be cosmetically significant. Harvests beginning in the middle of the donor area, offer the advantage of removing donor strips from the inferior side of the scar in the next procedure and on the superior side of the scar in a subsequent procedure, thus minimizing the chance that one will encroach on areas that are ultimately destined to lose their hair or become excessively sparse. Of course, the safest approach is not only to begin with a single donor strip in the middle of the donor area, where the hair is the safest long-term and most dense, but to excise the scar from any preceding session in the center of the new strip. This is the approach that Unger recommends whenever one is concerned about the patient developing type VI or VII MPB. Cole recognizes the rationale for this approach, but points out that the follicular density will always be lowest on both sides of the scar, particularly the inferior side. Therefore, excising the strip with the scar in its center might lead to a reduction in follicular yield.