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Pitfalls and Their Management
A number of problems arising in hair transplant surgery have been well described in the literature. Table 34.13 summarizes them, along with their most likely cause (though some etiologies may be multi-factorial) and methods for preventing and managing them should they occur.12,71,72
Table 34.13 Problems Encountered in Follicular Unit Hair Transplantation and their Management
| Problem | Cause | Prevention | Treatment |
|---|---|---|---|
| Syncope | Anxiety, Vaso-vagal reaction | Pre-medicate with valium or atropine, administer anesthesia with patient lying flat | Lie patient supine and elevate legs |
| Anxiety, palpitations | β 1- and α-adrenergic effects of epinephrine | Administer epinephrine slowly, pre-medicate with valium | Patience (the half-life of epinephrine is short); Lidocaine for arrhythmias |
| Hypertension and bradycardia | Epinephrine (adrenaline) interaction with β-blocker | Use selective β 1-blockers | α-adrenergic blockers; treat as cardiac emergency |
| Agitation, confusion, perioral numbness | Lidocaine toxicity | Use more dilute anesthetic mixture, use ring-blocks rather than local infiltration | Intravenous fluids, oxygen, ventilate, Diazepam; treat as cardiac emergency |
| Pruritus, urticaria, angioedema | Allergic reaction / anaphylaxis to drugs or food | Careful history | Oxygen, epinephrine (adrenaline) subcutaneously |
| Excessive bleeding | Elevated blood pressure, non-steroidal anti-inflammatory agents | Discontinue anti-platelet agents prior to surgery, continue anti-hypertensive medications day of surgery, pulse oximetry | Operate with patient seated; with elevated blood pressure, consider anti-hypertensives |
| Post-op edema | Surgical trauma, buffered anesthetic | Keep recipient sites small, pre- and post-op systemic cortico-steroids | Head elevation, additional post-op corticosteroids |
| Sterile folliculitis | Growing hair trapped by epidermal overgrowth | Keep grafts slightly elevated | Resolves spontaneously; incision and drainage if persistent |
| Cyst formation at graft site | Foreign body reaction to imbedded graft | Avoid piggybacking one graft over another in the same site | Incision and drainage, topical and/or systemic antibiotics |
| Bacterial folliculitis | Picking, scratching, poor hygiene, 2 0 to infected sterile folliculitis or cyst | Frequent post-op showering, topical cortico-steroids for pruritus | Topical and systemic antibiotics |
| Infected donor wound | Suture bites too large/tight; with post-op edema, causes vascular compromise | Harvest a narrower donor strip under less tension, change suturing technique | Systemic antibiotics; if severe, leave portion of donor area to heal by 2 0 intention |
| Widened scar in donor area | Donor strip too wide or placed too low, patient tendency to heal with stretched scar | Careful history, conservative donor strip located at level of occipital protuberance | Excision +/- (can worsen scar), Follicular Unit Extraction |
| Raised donor scar | History of keloids, racial susceptibility, incision placed too low | Careful history, patient selection, test biopsy | Intra-lesional corticosteroids |
| Persistent numbness or paresthesias in the back of the scalp | Transection of branches of the occipital nerves | Limit donor depth to deep subcutaneous layer, use tumescent anesthesia | Subsides spontaneously if the cut nerve branches were small |
| Hiccups | Possible injury to C2-C4, indirectly stimulating the vagus or diaphragmatic nerves | Limit donor depth to deep subcutaneous layer, use tumescent anesthesia | Chlorpromazine |
| Hair texture changes | Trauma to grafts, sebaceous glands removed in dissection? | Careful atraumatic dissection and placing, avoid trimming follicular units too close | Usually resolves spontaneously |
| Skin texture changes | Recipient wounds too large | Make wounds no larger that the equivalent size of a 19-g needle at the frontal hairline | Add coverage with one- and two-hair follicular units at the frontal hairline using very small sites |
| Hair loss in recipient area related to the procedure | Telogen effluvium73 | Possibly effective: small surgical wounds, limit epinephrine, pre-treat with finasteride | Terminal non-miniaturized hair should return spontaneously, finasteride |
| Hair loss in donor area | Strangulation of follicles by sutures, transection of follicles during harvest | Narrower donor strip, meticulous suturing techniques | Follicular Unit Hair Transplantation, Follicular Unit Extraction, local excision |
| Failure of transplanted hair to grow | Desiccation,74 crush injury,75 transection,76-78 grafts out of the body too long48 | Keep grafts well hydrated in an isotonic solution, careful microscopic dissection and handling | None |
Although FUT eliminates many of the shortcomings of older surgical hair restoration techniques, such as a “pluggy” look, a “moth-eaten” donor area or midline scalp reduction scars, poor aesthetic judgment and techniques that compromise graft growth can still lead to problems. Perhaps because FUT requires large numbers of grafts (using a significant portion of the donor area at one time), because so many staff members are involved in the process, and because some of the problems of small graft procedures are very difficult to correct, improperly performed follicular unit hair transplantation can pose a greater risk to patients than traditional grafting. The risk is compounded by the fact that many physicians perceive FUT as a safe, risk-free procedure and describe it to patients as such.
The remainder of this section will focus on some of the most common mistakes made by FUT practitioners, particularly in the areas of planning, hair transplant design and handling large numbers of small grafts. These problems and how they may be avoided are summarized in Table 34.14.
Table 34.14 Twelve Common Pitfalls in Follicular Unit Transplantation
- Operating on patients that are too young or prior to medical therapy
- Failing to identify low donor density prior to surgery
- Failing to identify a tight scalp
- Harvesting a donor strip that is too wide
- Placing the donor incision too low or too high
- Using a multi-bladed knife
- Crushing grafts during insertion
- Allowing grafts to dry
- Placing the frontal hairline too far forward
- Creating a hairline that is too broad
- Angling hair in the wrong direction
- Attempting to cover an area that is too large
Operating on Patients That Are Too Young or Before Medical Therapy
Patents in their early twenties have their flat adolescent hairline and original density fresh in their memory. A hair restoration designed with enough frontal and temporal recession to look good ones entire life will rarely satisfy a younger patient. Creating a density that is ideal for a younger person will not leave enough hair in reserve if there is further loss. In addition, at this age the extent of future balding is difficult to even reasonably anticipate. For these reasons, a hair transplant should rarely be considered in patients with androgenetic alopecia younger than 25.
Often a hair restoration doctor begins medical therapy and schedules surgery at the same time. However, if there is a possibility that using a medication, such as finasteride, can make hair transplantation unnecessary, then the medication should be used for at least a year before any decision on surgery is reached. Medication should be the first line of therapy for all younger patients with androgenetic alopecia, regardless of the degree of their hair loss.
Failing to Identify Low Donor Density Prior to Hair Transplant Surgery
Section 4, “Patient Evaluation and Surgical Planning,” stressed the importance of assessing patients’ donor supply with densitometry. A low donor density, generally less than 1.5 hairs per mm2, usually indicates that donor supply is insufficient to create adequate density or coverage, rendering the surgical hair restoration procedure inadvisable. An exception might be an older person with very conservative goals. High miniaturization in the donor area, particularly in a person under the age of 30, suggests Diffuse Unpatterned Hair Loss (DUPA) and is a contraindication to surgery.7
Transplanting patients with low donor density will also risk a visible scar if the hair is worn short. FUE is not appropriate in such cases, since it further limits the total available hair. In fact, since the contrast between bald and non-balding scalp in patients with low donor density is naturally low, their best option tends to be wearing their hair short, to decrease the contrast even more (rather than having hair transplant surgery).
Failing to Identify a Tight Scalp
Assessing scalp laxity is an underappreciated aspect of the patient evaluation, probably because it is difficult to quantify. However, a tight scalp severely limits the total amount of harvestable donor hair and can constitute a contraindication to surgery, except when hair transplantation patients have extremely conservative goals or are expected to experience only limited balding. The constraints that low scalp laxity impose generally manifest themselves after the first transplant session. Though laxity should be judged in the pre-op evaluation, the intra-operative assessment, made while suturing, is most accurate in predicting future difficulties. Therefore, every operative report should include a record of the ease of closure and intra-operative suture tension.7
Harvesting a Donor Strip That Is Too Wide
In large sessions, it can be tempting to take a slightly wider donor strip in order to conserve on length. A strip that is 25 cm by 1 cm, for instance, can be shortened by 6 cm if widened by just 3 mm–and yield the same amount of hair. However, a wide strip puts unnecessary tension on the donor closure and is probably the most common cause of widened scars. If larger sessions are appropriate, and the scalp lacks adequate mobility, the hair restoration doctor should consider a longer incision rather than a wider one.
If a wide donor strip has been identified as the likely cause of a stretched scar, it is advisable to wait at least eight months, to give the scar a chance to mature and regain some of its original laxity. When the next excision is made, the strip should measure at least 3-6 mm narrower than the previous one. Attempts to remove the entire width of the old scar invariably lead to a reoccurrence, or worsening, of the old scar. To facilitate healing, the new excision should extend to the hair transplant patient’s hair-bearing edge.
Unfortunately, attempts to re-excise scars commonly result in either no improvement or an even wider defect. For this reason, we have been using Follicular Unit Extraction to place hair directly into the scar as our primary treatment.
Placing the Donor Incision Too Low
The location of the donor incision greatly affects scalp mobility. The ideal position for it is in the mid-portion of the permanent zone that lies, in most people, at the level of the external occipital protuberance and the superior nuchal line. The muscles of the neck insert into the inferior portion of this ridge, so an incision below this anatomic landmark will be impacted by the muscle movement directly beneath it. A stretched scar in this location is extremely difficult to repair since re-excision, even with undermining and layered closure tends to heal with a wider scar. To compound the problem, one is more likely to cut through fascia with a low donor incision; and once the fascia has been violated, the risk of widening the scar rises considerably.36
In addition to the slightly greater risk of a widened scar, the main problems of harvesting hair too high are lack of permanence of the transplanted hair (since it may be subject to androgenic alopecia) and future visibility of the scar were the donor fringe to narrow further. Incisions made too high are best left untreated, unless the scar is wide and poor surgical technique has been identified as the cause. The temptation to transplant permanent donor hair into a high scar should be resisted, as progressive balding would isolate the hair-bearing scar, presenting new cosmetic problems.
Interestingly, in the case of young hair transplant patients with traumatic scars and hair-loss patterns that are still unclear, Follicular Unit Extraction can function as a hedge against this risk. If the hair is harvested from the immediate vicinity of the scar, any future balding will affect the transplanted hair in the scar at the same rate as the hair surrounding it.
Using a Multi-Bladed Knife
In order to save time, a hair restoration doctor performing large transplants may use a multi-bladed knife (one with three or more blades) for harvesting donor tissue. The resulting pre-sliced multiple thin strips are much easier to work with than a single intact strip. Unfortunately, harvesting this way causes unacceptable levels of follicular transection while destroying the naturally occurring follicular unit and is therefore incompatible with FUT.10
Crushing Grafts During Insertion
Proper placing technique necessitates the use of forceps to grasp the graft by the fat below the bulb or by the dermis alongside the hair shaft in order to avoid damaging the germinative components of the follicle. Though placers often exercise enormous care while initially grasping the graft, there is a tendency to become rougher when repositioning the forceps for further inserting, replacing a popped graft or transferring grafts from the holding solution to the fingers. Since follicular units and other small grafts are particularly susceptible to crush injury after a hair transplant, improper handling can more than negate the benefits of careful stereo-microscopic dissection.73,74
Allowing Grafts to Dry
An elegant study using electron microscopy has shown that desiccation is by far the most significant form of injury to grafts and makes them much more susceptible to other forms of injury, such a mechanical trauma and warming. Grafts should therefore be kept well-hydrated with chilled isotonic solution (such as Ringer’s lactate) from the moment the tissue is harvested until the time they are reinserted into the scalp.75
Placing the Frontal Hairline Too Far Forward (Too Low)
Despite the fact that individual follicular units at the hairline in themselves look natural, their proper placement is no less important than in traditional grafting. The frontal hairline should be placed no lower than 1.5 cm above the upper brow crease.1,8 Particularly if the underlying skin is normal, follicular units placed too low can be removed with an alexandrite (755 nm) or diode (800, 810 nm) laser. Electrolysis is more difficult and time-consuming with transplanted follicles, but should also be considered. Punch excision is too imprecise for very small grafts and risks scarring.
Creating a Hairline That is Too Broad
Since significant temporal recession is characteristic of the normal adult male hairline, a broad, flat transplanted hairline will not age well and can cause cosmetic problems if baldness becomes extensive. The treatment is the same as with low hairlines, but it should be noted that if grafts larger than follicular units were used, and/or if there is scarring of the recipient skin, punch excision with reutilization of the hair may be indicated.
Angling Hair in the Wrong Direction
As noted earlier, in the front and top part of the scalp, hair grows in a distinctly forward direction, changing to a radial pattern as it approaches the crown. It emerges from the scalp at an acute angle, with the hair lying practically flush to the skin at the temples.
There has been a tendency among some hair restoration doctors to transplant grafts perpendicular to the skin–probably due to the fact that the mechanics of the old plug procedures made sharp angling technically difficult. The cosmetic consequence of this is most apparent at the frontal hairline. When the hair is perpendicular, the viewer’s eye is guided to the base of the hair shaft where it inserts into the skin; conversely, when hair is transplanted in its natural, forward-pointing position, it is bowed by grooming and the eye settles on the body of the hair shaft.
When grafts at the frontal hairline are transplanted in a radial direction, combing the hair in any style becomes problematic and invariably results in an unhappy patient. As with low or broad hairlines, hair that is angled in the wrong direction, particularly in the frontal hairline, should be removed.
Attempting to Cover an Area That Is Too Large
Attempting to cover an area greater than the donor supply can adequately fill may leave cosmetically important areas thin or untransplanted. In general, the first region to bald is the area where you should be most hesitant to transplant. Recession at the temples and thinning in the crown are usually the earliest manifestations of baldness, but they are acceptable, especially as patients age, so these areas may be left untransplanted. The central forelock region, however, is generally late to bald, but when balding occurs, the patient loses the frame to his face and its restoration becomes essential.7
Whether or not these areas need coverage at the time of the initial transplant, an adequate amount of hair must always be reserved for critical areas, such as the forelock and top of the scalp. If donor reserves are limited, the transplantation of less critical areas should be postponed or avoided all together.7
Summary
Developed within the past decade, Follicular Unit Transplantation has emerged as both the standard and the cutting edge in hair transplant surgery. In conserving donor hair, achieving optimal coverage and creating a natural look, FUT represents a considerable advance over earlier methods of hair restoration. Appropriately, it also demands considerably more from its practitioners. Surgical hair restoration teams must develop the skill and stamina for the delicate handling of large numbers of follicular unit grafts, while surgeons must cultivate a keen aesthetic sensibility with regard to transplant design and graft placement.
In view of the psychological aspects of hair loss, Follicular Unit Transplantation requires a thorough preoperative assessment to understand the patient’s expectations, a careful examination to determine if surgery is appropriate and, most importantly, the establishment of realistic goals. If the surgical route is chosen, meticulous attention to detail is required in every aspect of the procedure so that these goals may be realized. It is a daunting task for the hair restoration doctor and surgical team to develop the necessary expertise for perfecting Follicular Unit Transplantation; but when they do, their work can benefit patients for their lifetime.
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This article was published in Surgery of the Skin; editors: Robinson JK, Hanke CW, Siegel DM, Sengelmann RD, Robert M. Bernstein, M.D., Follicular Unit Hair Transplantation, Chapter 34, pages: 549-574, and is posted with permission Elsevier Mosby Inc., London UK. 2005.
