The Donor Area: Out of Sight, Out of Mind

Having discussed follicular unit transplantation, hair density and characteristics, and some of the older techniques of hair restoration surgery, let’s now lend our full attention to the donor area. This is often minimally considered, by patients and by surgeons, as it is covered by hair, and seldom seen by the patient or, hopefully, by anyone else. It is, however, of utmost importance for achieving the highest level of cosmetic excellence; respecting and protecting the donor reserves is vital in planning for future hair loss and possible future procedures.

Donor Area Location

If you have ever seen a man with Class VII balding, and we all have, you have seen a graphic representation of the limits and confines of the donor area. This is the hair zone that is considered permanent. With rare exceptions, this rim of hair remains even in the most advanced cases of male pattern baldness. The boundaries of this zone extend from in front of the ears, around the temples, and to the back of the head (figure 1). The hair at the temples may recede back toward the ear, and the balding area of the crown may dip quite low into the occipital area, at the back of the head. We must always assume that any man considering hair transplant surgery will eventually advance to this Class VII level for balding; it’s easy to understand why. Visible scars may be revealed if the baldness advances, and donor tissue has been taken too high, too low, or too far in front of the ears.

Fig. 1 Safe Donor Area From Walter Unger, MD

Scarring in the Donor Zone

Another problem involving scarring in the donor area is that of the widened scar. In a patient without a systemic disease or drug use that retards healing, a well-closed, non-infected incision should eventually appear as a thin white line, well camouflaged by the hair. Sometimes, however, this is not the case. For example, if the donor strip is taken too low in the back of the head (toward the top if the neck), a widened scar can result. Often, as men get older, the inferior hairline (at the neck) will move higher. If this is the case, a low, widened scar can be a cosmetic liability.

In addition, certain patients with an inborn weakness of collagen or defects in the building of new collagen (collagen is the connective tissue protein of which ligaments, tendons and scars are made) may develop wider than normal scars regardless of how well the incision is closed. Surgical wisdom has always taught us that closure of any wound under tension (such as a wide incision or in taut tissues) can lead to a widened scar. Therefore, we always attempt to make the donor strip as narrow as we can, based on the tightness or laxity of the patient’s scalp. Indeed, this is one of the problems seen after scalp reductions and/or multiple transplant procedures: a tight, unyielding, fibrotic donor area. This is why hair restoration surgeons like to see patients with lax, loose scalps. Occasionally, though, a paradox exists. This is when patients who do have scalp laxity heal with widened scars. It is possible that these patients may have one of the aforementioned collagen defects. In short, careful evaluation and planning can result in fine, cosmetic scars in most cases; there are cases where the scar is sub-optimal regardless of the surgeon’s skill.

Many of us today see the results of older methods of donor harvesting; often, patients with the older, "pluggy" look of the past seek transplantation to remove or disguise the old round grafts, or their balding may have progressed to the point that they desire grafting to newly bald areas. When the outmoded harvesting techniques of punch grafting with open donor healing were used, the result was a "shotgun" or "moth-eaten" appearance that is cosmetically quite displeasing. This type of scarring also renders further strip harvesting difficult, to say the least, and it greatly complicates the estimation of needed strip size for a given number of grafts. Similar problems arise when the patient’s donor area has been subjected to multiple small strip harvests, with a "stairstep" pattern of linear scars, or extensive plug harvesting that was then sutured in a "semi-sawtooth" pattern.

We have spoken in previous sections about the necessity of preserving the donor area for possible future transplant work. Even if an individual is older, has seemingly "stable" baldness, and is satisfied with his hair transplant outcome, the day may arise when his hair loss accelerates. Then, if his donor area has been conserved, he may have sufficient reserves for additional procedures. If not, then his options are limited to camouflage, hairpieces, or living with the appearance of baldness.

We also discussed single strip harvesting as the technique with the most "hair-conserving" potential, and we deemed large sessions of follicular units as probably the most expedient and efficient method of transplantation. If these techniques are properly utilized, then the fewest hairs will be damaged at the time of harvesting. Furthermore, the integrity of the donor area will be preserved, scarring will be minimized, and preservation of donor reserves will be maximized for possible use in the future. This is an integral part of the essential long term planning process that will be discussed at length in a later section.