Follicular Unit Excision Complications

73 Follicular Unit Excision Complications

Conradin von Albertini

Summary

Follicular unit excision (FUE) complications are caused by either the large number of excisions needed with this technique (“donor issues”) or the high vulnerability of FUE grafts (“graft issues”). While usually not catastrophic, FUE complications can have a detrimental cosmetic impact on the patients, and in some cases can create problems that are virtually uncorrectable. This chapter not only describes the typical complications in FUE, but also offers suggestions as to how they might be prevented and managed. The chapter first discusses the various donor issues of FUE, for example, white dots, surgical pattern, donor effluvium (shock loss), donor necrosis, and local anesthesia overdose. Then the chapter discusses the graft issues an FUE surgeon might encounter, for example, buried grafts and various graft injuries leading to the dreaded failure of poor growth (transection, desiccation, crushing, etc.). The chapter concludes on a quality principle called “MINIMAX,” which stands for “minimizing donor microtraumas per session and maximizing the care of the sensitive grafts.” Under this precept, good FUE practice goes beyond excision and has implications for the entire procedure from planning to placement quality.

Keywords: FUE complication overharvesting donor effluvium shock loss donor necrosis local anesthetic overdose buried graft donor cyst transection crushing

Key Points

•Follicular unit excision (FUE) complications are caused by either the large number of excisions needed with this technique (“donor issues”) or the high vulnerability of FUE grafts (“graft issues”).

•To prevent FUE complications, the surgeons need to minimize microtraumas in the donor area and maximize the care of the sensitive grafts.

•Good FUE practice includes prudent planning, fast and meticulous excision, and outstanding placement skills.

73.1 Introduction

Hair restoration surgery (HRS) is a low-risk procedure in which severe complications are a rarity and mostly preventable.1^,² The same goes for the increasingly popular technique of follicular unit excision (FUE).³^,⁴^,⁵ However, the FUE technique creates a unique set of complications.⁶ As they can have a detrimental cosmetic impact on patients, it is important to understand and mitigate the risks of the method. Furthermore, the increase in FUE procedures being performed by untrained physicians or assistants without supervision is likely to result in a more significant number of serious complications.

This chapter focuses on FUE complications, which, by definition, arise because of the particular nature of the excision process. As compared to strip surgery, FUE has two remarkable features:

•It leaves a large number of small excision sites distributed over a relatively large donor surface.

•It produces particularly delicate grafts, which have minimal surrounding protective tissue.

The two characteristics of FUE offer a meaningful way to categorize the complications according to their principal causes (Table 73.1):

•“Donor issues” include developments that are provoked by the sheer number of the excisions needed.

•“Graft issues” include all risks of handling (removal, storage, and placement) of the vulnerable FUE grafts.

Table 73.1 Overview of the complications of follicular unit excision (FUE) procedures as discussed in this chapter

Donor issues

Graft issues

Overharvesting

Harvesting outside SDA

White dots/surgical pattern

Donor effluvium (shock loss)

Donor necrosis

Anesthetic overdose

Buried grafts/donor cysts

Graft injuries/growth failure

•Removal: desheathing, transection, plucking, capping

•Transit: desiccation, time out of body

•Placement: crushing, hooking

Abbreviation: SDA, safe donor area.

Following this logic, this chapter provides a short description of each complication, followed by suggestions for their management and prevention (Video 73.1).

73.2 Donor Issues

A major challenge of FUE lies in managing the large number of excisions. The sheer numbers of excisions are at the root of most donor complications.

73.2.1 Overharvesting/Donor Depletion

One of the best known FUE donor complications is overharvesting or donor depletion. It happens when surgeons—in the quest for a large number of grafts—remove too many follicular units (FUs). They deplete the donor site, which leads to a “see-through” or even “moth-eaten” appearance of the back of the head (Fig. 73.1). The cosmetic harm can be significant, especially when there is no reserve of scalp hair left for corrective procedures.

Fig. 73.1 Depleted donor area with a moth-eaten appearance.

Overharvesting results from poor planning when there is insufficient donor hair for the projected coverage of the recipient area. Not surprisingly, the risk of a mismatch between the actual donor and the planned recipient increases with the number of grafts per session.

Management

The remedy is camouflaging with another FUE procedure. When there is not enough scalp hair left, the surgeon can use beard or body hair transplants or even scalp micropigmentation (SMP).³

Prevention

Overharvesting is fully preventable with a prudent, conservative treatment plan and common sense. There are several programs available that help FUE surgeons evaluate the overall density and the number of excisions, as well as number of hairs per graft, which are prudent to harvest. Surgeons need to allow proper spacing between the harvested follicles and set a reasonable limit to the number of grafts per session, which is believed to be at maximum about 3,000 FUs in patients with high donor density and less in those with lower density. Furthermore, it is also essential to leave some reserve of donor hair for future procedures, especially in young patients.

73.2.2 Harvesting Outside the Safe Donor Area

Another concern triggered by the mere number of excisions needed in FUE is the harvesting of hair follicles outside of the safe donor area (SDA).7 When spreading out the excisions, the surgeon has some limitations in the ability to define the borders of the SDA reliably, thus risks harvesting nonpermanent hair follicles. Again, the risk increases with the number of excisions. In some instances, however, stepping outside the SDA is a deliberate act, for example, to feather out the donor fringe, or to take advantage of stable hair loss in older patients.

The negative cosmetic impact can be significant as over the long term the nonpermanent hair falls out and the small punctuate scars in the donor may become visible. At the best, the recipient area thins out, while at the worst, irregular patches of balding appear.⁷

Management

Overharvesting may be remedied by camouflaging by various means including styling or SMP.

Prevention

A conservative, cautious treatment plan significantly reduces the risk of extending beyond the borders of the SDA. When planning an FUE procedure, the surgeon should analyze the donor area in detail.⁸ Especially in first procedures and younger patients, the donor zone should be defined restrictively. When harvesting outside the SDA on purpose, it is advisable to mix permanent and nonpermanent grafts in the recipient area to avoid the potential development of bald patches over time,⁷ and, if indicated, prescribe adjuvant medical therapy to control the progression of balding. Another approach suggested by Robin Unger is to use less permanent grafts in the periphery of the recipient area, primarily in the anterior and posterior borders so that the likely recession over time will look more natural.

73.2.3 White Dots/Surgical Pattern

The FUE punch leaves hundreds of small full-thickness wounds in the donor. After healing by secondary intention and the ensuing tissue retraction, they form hypopigmented scars called “white dots” (Fig. 73.2). In most cases, they are nearly invisible and do not require any remedial action.⁹ White dots, however, become more significant when they are larger in size and exist outside the SDA and may become visible one day, or when they form a clear surgical pattern, for example, lines or squares. Surgical patterns appear when the surgeon excises many grafts too regularly or only from a limited area. The cosmetic impact can be substantial, especially in a depleted donor area.

Fig. 73.2 White dots in the donor area.

Management

Affected patients can be advised to wear longer hair or be offered camouflage by other available techniques.

Prevention

Using the smallest possible punch can help reduce the white dots’ size. To prevent patterns, the surgeon should harvest grafts randomly and, when necessary, feather the outside borders toward the rims of the donor area. However, surgical patterns are inevitable when only strips of the donor hair are shaved (Fig. 73.3). Thus, partial shave FUE should be provided reluctantly and only to patients ready to wear their hair longer and after proper patient counseling. Another suggestion is to excise fewer grafts per area than average to prevent a discrepancy in density with the nonharvested donor area. A more challenging alternative, without any risks of resulting discernable patterns, is to offer unshaven FUE.¹⁰