Design in the Creation of the Recipient Area During Hair Transplants

Natural Pattern

To a large extent, the correct template for hairline placement, hair distribution, and density has already been supplied by nature. The closer one follows the pattern set by nature, the more natural the hair restoration will appear. A hair transplant no matter how dense or how perfectly executed will look artificial unless it produces a look that others can recognize as one they had seen before. Just as the follicular implant attempts to mimic the way hair grows in nature on a microscopic level, the overall design of the follicular implantation should strive to mimic nature on a gross level.

The power of "The Isolated Frontal Forelock" recently described by Marritt and Dzubow lies in the fact that they identified a pattern seen in nature that was reproducible within the limits of the patient's donor supply. However, the use of larger grafts for the dense posterior component limits the amount of available donor hair, and creates a natural look only when disguised by the anterior component. The main limitation of flaps and scalp reductions (even in the best of circumstances where there are no complications) are that although they achieve high density, there is no natural counterpart to the distribution they produce. Flaps bring the patient's donor density to the frontal hairline, with a sharp demarcation anteriorly and posteriorly, a pattern never seen in nature. This area of high density must then be supported by a similar density around it to look natural and, of course, if the patient had enough hair to accomplish this, he wouldn't have needed hair restoration in the first place. The scalp reduction, although appealing on a superficial level ("remove the bald area so there will be less area to transplant"), violates the same rules of nature as does the flap. A scar is placed in an area that should have light coverage (if any), the direction of hair is changed, the pattern of future balding of that crown will be altered, and donor density is decreased. In effect, scalp reductions are a "crown transplant" and thereby reduce the hair available for the cosmetically more important front.

We feel that the optimal way to plan a hair transplant procedure would be to first assess the patient's present pattern of loss and to anticipate his possible future pattern (considering his present age and familial hair loss patterns) using the worst case scenario as a reference point. Next, determine a person's total donor reservoir of hair (taking into account absolute donor density, degree of miniaturization, hair groupings and scalp mobility). Then, carefully analyze his specific hair characteristics which affect the appearance of fullness and naturalness (such as wave, hair shaft diameter and skin/hair color contrast). With this information in hand , one can realistically plan how far back in time one can go along his hair loss continuum, given the patient's particular resources.

For example, a 55 year old Norwood Class 4 with a donor density of 2.3 and 20% miniaturization in the donor area and wavy hair, may be safely restored to a Class 3 using 1700 follicular units. On the other hand, a 23 year old Class 5 patient with a donor density of 1.9 and 35% miniaturization in the donor site, with fine, straight hair should be restored to a Class 3 Vertex, rather than a regular Class 3. using 1500 follicular units. In this situation, we would use 1500 follicular units and leave the crown untreated. If he were to bald extensively, he might end up years later with an isolated tuft of hair in the crown, without enough donor reserves to complete the hair transplant.

Frame the Face and Spare the Crown

The patient judges the success of his hair restoration by its ability to enhance his appearance, which is in large part based upon the ability of keeping his facial features in proportion. In this regard, the second important element in proper planning is to make every effort to "frame the face". Transplants which add density to a hairline placed too high (in the hope of conserving donor hair) only accentuate the patient's baldness by elongating a bald forehead. It frames the forehead rather than the face. We generally place the frontal hairline one fingerbreadth (2cm) above the uppermost brow wrinkle (mature hairline). It is important to differentiate this from the patient's original hairline which sits directly above the brow wrinkles, lacks bitemporal recession, and should not be used as a landmark for planning the hair transplant. When the donor supply is limited, it is much better to compromise towards the crown than to compromise the critically important position of the frontal hairline.

The decision to transplant the crown is an important one, because compared to other areas of balding, it is the least visible but occupies the greatest area. The progressively balding crown can produce huge demands upon the donor supply, and because this area is also the least stable, hair must always be reserved for this eventuality. Furthermore, the crown expands centrifugally, rather than in the predominantly anterior-posterior direction of the front and top, with the center of the crown always having the least amount of hair and being surrounded by areas of increasing densities. Because of this, any hair placed in the center of a balding crown can result in an island of hair surrounded by a moat of bald skin. To correct this, hair of increasing density must be added around it to be aesthetically balanced, consuming vast amounts of hair that could be better saved for the front. Because of these issues, we generally reserve treatment of the crown for older patients with above-average donor density and stable hair loss of Class 3 Vertex, Class 4, and Class 5, or patients of Norwood Class 6 with high donor density and good scalp mobility. If extensive balding is a possibility, it is always best to treat the crown as an extension of the top, rather than as an isolated region to ensure that you will not be short of hair if the intervening region were to bald.

Eliminate Contrast

The next element in planning the follicular transplantation is the elimination of contrast. We have already gone to great lengths to illustrate how eliminating contrast on the "micro" level is important, i.e. eliminating the contrast between the individual graft and the surrounding skin. It is equally important to eliminate contrast on the "macro" level, i.e. between one part of the scalp and the other. One of the most striking features about the balding process is that practically all of the Norwood Class A patients look aesthetically worse than their regular Norwood counterparts. In fact, most Norwood Class A patients look worse than patients in the next higher Norwood Class, in spite of the fact that those patients have more hair. Thus, a Norwood Class 4A often looks worse than a Class 5, and a Norwood Class 5A often worse than a Class 6. Clinically, we find that the Class A patients are often the most distraught over their hair loss and benefit most from the hair transplant procedure.

The reason for this is simple. In the Class A patient, there is the greatest contrast between the hair bearing area and the totally bald scalp. Curly or wavy hair increases the clinical appearance of density. In the regular Norwood classes, a curly or wavy haired patient will look less bald, because any slight coverage on top will be magnified by the character of the hair. In contradistinction, curly or wavy hair will make the Class A patient look more bald, because in this patient it will accentuate the contrast.

The same reasoning helps to explain why an older patient looks better as a Class 6 than a younger patient. The younger patient has had patterned androgenetic effects causing hair loss in the bald area. His donor density is essentially unchanged. The older patient, however, has had hair loss due to both patterned androgenetic balding as well as loss due to the aging process itself, the latter affecting the "permanent zone". In addition, the older patient has a higher degree of miniaturization in the donor area, which further reduces the contrast.

Furthermore, the younger patient with higher donor density will look balder than his Norwood counterpart with lower density. In patients of all ages where the bald area is too extensive to be covered by adjacent hair, the patient's cosmetic appearance is generally enhanced by keeping the hair short, which is just another means of decreasing the contrast between the two areas. Fortunately, the higher the density of the permanent zone, the worse the bald areas look in comparison, but the more hair there is available to transplant. In a sense, hair transplants do not add hair, they decrease contrast by moving hair around.

Angulation

The single most useful clue to proper angulation is to observe the patient's existing hair. Even in very bald areas, a few vestigial hairs will often indicate the original orientation of the terminal hair. When this information is not available, the safest direction to follow, aside from the crown, is generally forward. The majority of hair anterior to the crown points forward with the angle becoming more acute anteriorly. The direction of the frontal hairline is also forward, rather than radial, and only deviates significantly from this as one approaches the temples. Horizontal placement of the frontal hair is usually appropriate, regardless of the slope of the forehead.

Follicular implantation provides almost unlimited freedom in choosing the angle at which the future hair will emerge from the scalp. This is because the mechanical forces facing the larger grafts placed at acute angles do not affect the follicular implant. The delicate swirl of the crown, the abrupt directional changes of the cowlick, and the sharp angulation of the temples, can all be re-created with follicular implants. The challenge is not merely creating these angles, but observing the myriad of patterns seen in nature so that this variety can be duplicated for our patients.

Distribution

In almost all cases of balding, there is a rationing of donor hair due to the necessity of covering an ever expanding recipient area with a much smaller, but finite, donor supply. We try to evenly space the individual units in a random rather than grid-like pattern and always try to increase the density in the areas of cosmetic importance. In doing so, we remember the adage "To cover a baseball field with grass, use seed rather than sod....., and if you only have a limited amount, use it in the infield."