Follicular Unit Excision for CorrectiveWork

71 Follicular Unit Excision for Corrective Work

Antonio Ruston and Luciana Takata Pontes

Summary

For some cases, corrective procedures are only possible with the use of the follicular unit excision (FUE) technique. When donor hair for repair from strip surgery has been exhausted, FUE has enabled the utilization of additional scalp hair from outside the traditional safe donor area. It also allows for the careful excision of donor hair from in-between scars from previous punch or strip harvesting procedures. In addition, body hair can be used for repair. FUE also allow for the removal and recycling of unaesthetic, pluggy grafts from previous surgeries. Scalp micropigmentation (SMP) can be used as a complement to FUE by camouflaging linear scars and giving the impression of more volume in depleted donor areas. Corrective cases can be very complicated and challenging. They present with many difficulties such as low density in the donor area and preexisting scars. Grafts can be more difficult to extract due to hair angle distortion due to existing scars or improperly angled grafts. The surgeon must understand these difficulties and be aware of their own skill level and not hesitate in sending these cases to a more experienced colleague if necessary.

Keywords: corrective FUE difficult FUE cases depleted donor FUE SMP and FUE FUE into scars

Key Points

•Follicular unit excision (FUE) can be used as a good alternative to repair previous hair transplant procedures, but there are some difficulties associated with it.

•The use of the scalp micropigmentation (SMP) can help the final result of FUE corrective procedures.

•Corrective cases are usually harder and more challenging and must be treated with experienced hands.

71.1 Introduction

For some cases, corrective procedures are only possible with the use of the follicular unit excision (FUE) technique. Often removal of a donor strip may no longer be possible due to multiple or widened scars, tight scalps, and depleted donor supply.1^,² In these situations, FUE allows us to harvest of additional donor hair, which can be used for repair, from both scalp and body sources not traditionally available by strip harvesting. FUE has also improved our ability to remove and redistribute unaesthetic pluggy grafts from previous surgeries. Scalp micropigmentation (SMP) can be used as a complement to FUE by camouflaging linear scars as well as giving the impression of more volume in depleted donor and thin recipient areas. It should be emphasized that corrective cases can be very complicated and challenging. They present with many difficulties such as low density in the donor area, preexisting scars, and grafts that can be more difficult to extract due to hair angle distortion due to existing scars. The surgeon must understand these difficulties and be aware of their own skill level and limitations. They should not hesitate to send these cases to a more experienced colleague if necessary (Video 71.1).

71.2 Benefits of Using Follicular Unit Excision for Repair

71.2.1 Use of Hair Outside the Traditional Safe Area

FUE permits the utilization of greater donor area in the scalp than the “traditional” safe area because it somewhat expands the possible regions for donor harvesting. The nape of the neck, the area below the occipital protuberance, the upper lateral areas, the supra-auricular area, and temples can all be possible donor regions.² Although these areas may prove to have less longevity than the “safer” conventional donor area, the hairs transplanted can provide more hair during the younger years when it is more important to patients. Additionally, choosing a two- or a three-hair follicular unit (FU) to harvest from these areas will increase the chance that they last over time.

71.2.2 Use of Hair from between Previous Punch or Strip Scars

Another potential advantage of FUE is the possibility of excising between scars from previous punches or strip procedures. Even when the donor area is largely depleted from big punch harvesting, it is possible to perform a conservative harvest using very small FUE punches (Fig. 71.1).³ One has to proceed very carefully in these scenarios because the added punctuate scars from FUE, if overdone, can worsen the appearance of an already overharvested donor area. Often the goal is a more homogenized look or even that can be created by slightly thinning the unharvested area and slightly thickening scarred or depleted areas

Fig. 71.1 Follicular unit excision (FUE) used for extraction between linear scars (a) before harvest and (b) after harvest. FUE used for extraction between punch scars (c) before harvest and (d) after harvest.

71.2.3 Use of Body Hair

Body hair, mainly from the beard, can be used for hair transplant, but preferably this is utilized in scenarios in which the scalp donor area is depleted. Due to the morphological dissimilarity of body hair to scalp hair, the central and caudal regions of the scalp are prioritized for increasing density when using beard hair (Fig. 71.2).⁴^,⁵^,⁶ Body hair from areas other than the beard, where the hair is finer, can be used both to soften hairlines and as a last resort for density and camouflage when all other sources are depleted.

Fig. 71.2 (a) Patient with severe depletion of the donor area. (b) Beard follicular unit excision (FUE) used as donor source. Note the difference in thickness between scalp and beard hair. (c, d) Midscalp and crown before and after beard hair.

71.2.4 Ability to “Carefully” Harvest Hair from Areas Where a Strip Scar may be Visible

One indication for the FUE procedure is the patients with a low density or caliber in which a linear scar has a greater risk of being evident, especially when a short haircut is preferred. It is also these situations that require control on the part of the surgeon not to harvest too much from a donor area that already has low density. The use of concepts like coverage value is particularly important for donor management in these situations.

71.2.5 Ability to Punch Out and Redistribute Unnatural, Pluggy Grafts to Repair Hairlines

FUE is very useful for repairing unnatural hairlines. The two most common causes of unnatural-looking hairlines are poor design or pluggy-looking grafts on the hairline. Poorly designed hairlines can be too low, too straight, or have aggressively filled-in blunted corners. In the past, it was large 10- to 12-hair grafts on the hairline that looked unnatural. However today even small, two- and three-hair grafts will look pluggy and unnatural if pitted, compressed, poorly angled, or in the wrong direction. In addition, only fine one-hair grafts should the most anterior border of the hairline. Unfortunately, with FUE (unlike follicular unit transplantation [FUT]) grafts are not routinely examined microscopically, and all too often two- and three-hair grafts are mistakenly placed in the hairline.

In many cases, simply adding grafts for camouflage does not work, and can even make things worse by wasting grafts and making the hairline more noticeable. By using FUE, unnatural grafts can be removed and recycled into other areas.7 Removing these grafts also creates a fresh palate in which to create a new natural hairline. Sometimes laser hair removal is combined with FUE to remove all the hairs. See Video 71.2for discussion of individual graft removal versus surgical excision for hairline repair.

71.2.6 Ability to Use Grafts Obtained and Use Grafts Recipient Area in Rare Situations

Dr. Seastian Yart has described “rare” situations in which obtaining donor grafts from the recipient area to temporarily cover a defect while a patient is young may be a prudent approach rather than wasting permanent donor hair. For example, in a young patient with a scar in his crown whose long-term hair loss pattern is not known, it may be safer to use some hair from the adjacent recipient area to cover the scar area. In the future, if he or she progresses to a type 6, he or she will be left with a normal pattern that can be left as it is or be treated depending on the donor supply at that time. This has been referred to as potentially androgenetic hair transplantation or PATH.⁹

71.3 Difficulties Using Follicular Unit Excision for Repair

There are some difficulties that surgeons might face during FUE corrective work. Low density in the donor area is the first among them. Besides taking extra care to not further deplete the donor area, it is extremely important to know how to optimize the result, harvesting wisely what may still be excised from the donor area. In these cases, it is important to be a “sharpshooter” with a single bullet.² The use of the coverage value concept may help with determining maximum safe donor that can be harvested.

The greatest skills to develop at this point are “how to make less look like more” and which strategy will create a greater impact. For example, when donor is limited, the author believes that much improvement can be done with minimal grafts by removing and recycling grafts from hairline and then using the minimal amount necessary to make it look natural (Fig. 71.3). Focusing density increase on frontal tuft area, adding a slight widows peak, and adding back conservative temporal points can all create major aesthetic changes with limited donor usage. Then the beard and other sources of body hair can be used combined with the remaining scalp hair to increase density behind the hairline to recreate a more natural density gradient. Titrating density to a “homogenized look” by making donor and recipient areas more equal also helps.