Controversies in Hair Transplantation

Unger’s safe area

SDA was first suggested by Unger et al.[13] in 1994 and this continues to be the global standard. They had described an SDA for over 80% of patients (under the age of 80 years). Such an area would consist of more or less a parallelogram in the parietal–occipital area, whose inferior border would be chosen by the surgeon on the basis of ≥10 hairs per 4-mm diameter circle [Figure 1]. This number would provide a “cushion,” allowing for a subsequent decrease in density with aging to eight hairs per 4-mm diameter circle. (The number of hairs per 4-mm diameter circle could be increased if one wanted to approach the donor area in an even more conservative fashion.) The superior border of the parallelogram would be 71.7mm superior to the inferior border. The anterior border of the parallelogram would similarly contain at least 10 hairs per 4-mm diameter circle and would angle somewhat anteriorly, parallel to the postauricular hair margin. A narrower more or less parallelogram would sit on the inferior one, with its posterior border beginning in the midparietal area. Its anterior border would be 28.6mm anterior to a line drawn vertically from the tragus and would be parallel to the temporal hairline, unless there were good reasons to suspect the area anterior to the tragus would not remain sufficiently dense over the long term. This superior parallelogram would be 12.3mm high (again subject to clinical findings and family history). Its superior border would drop somewhat inferiorly as it progressed posteriorly to meet the midline point of the safe occipital donor area. Lastly, in the midtemporal area, the “safe” donor area would extend 55.6mm superior to the superior parallelogram and then descend on a line drawn to meet the SDA in the midparietal area. It is important to point out that this design incorporates permanent hair whose long-term density would be eight hairs or more per 4-mm diameter circle, but that according to this criterion less dense permanent hair would persist superior and inferior to these boundaries in virtually all patients. Some of this less dense hair in some patients could be used as additional donor material if it were necessary.[13]

Close

Figure 1

Safe donor area illustrations. (A) Alt’s safe donor area, (B) Unger’s safe donor area, (C) cole’s safe donor area, (D) Cole’s FUE safe donor area

Export to PPT

The aforementioned noted boundaries are not suggested as perfectly safe for all patients, but represent the implications of the only objective scientific evaluation of this area. On the basis of that investigation, they would be very safe in approximately 80% of patients under the age of 80 years. More restrictive areas can be chosen, for example, if one prefers to plan for patients who might live 80 or more years or if the patient has a father or maternal grandfather with Type VII male pattern baldness.

Alt’s safe area

Alt suggested that a line drawn perpendicularly from the external auditory canal should define the anterior border of the safe area [Figure 1].[14] In majority, the anterior border of this SDA was 6.5 to 7cm wide and steadily narrowed posteriorly. A horizontal line drawn from a point 2cm superior to the reflection of the skin of external ear and the scalp to the point where the line intersects the midline of occiput defines the superior border of SDA. Alt had also suggested that at least 2.5cm of unharvested permanent hair should remain superior to the most superior donor area to provide adequate long-term camouflage of donor scars.

Cole’s safe area

Cole suggested a definition of the donor area for FUE procedure based on his study on 64 Caucasians and 30 Asians.[14] According to Cole, the total permanent donor area was 203cm². He proposed a subdivision of donor area into 14 regions: 8 major regions (richer in follicles) and 6 minor regions [Figure 1]. The regions 1 and 5 measure 3.5×5cm, regions 2, 3, 4, 6, 7, and 8 measure 3.5×6cm, and the minor regions 9–14 measure 3.5×2cm.

Bernstein and Rassman definition of SDA

Bernstein and Rassman[15] have suggested that the SDA consist of approximately 25% of the scalp and that only half of these donor area could be removed.[3] They have suggested that a clear demarcation of the inferior border of the donor area is slightly controversial, as the inferior margin may move upward with the passage of time.[3]

SDA definition based on parietal whorl by Park

Park et al.[16] defined the SDA in relation to parietal whorl (PW) involving 1008 Korean adult males. They concluded that the progression range of vertex alopecia to the occipital side is the most critical factor in establishing the SDA. The objective and scientific prediction of the progression of vertex alopecia to the occipital side will allow the anticipation of the maximum progression range of vertex alopecia and the available SDA of each patient. According to this study, when the PW is anteriorly positioned, vertex alopecia initiates more anteriorly, and when the PW is positioned closer to the occipital side, vertex alopecia progresses posteriorly. Thus, the progression range of alopecia is verified to occur more extensively when the PW is positioned closer to the occipital side. Even though the PW may be anteriorly positioned, if the alopecia of the vertex area progressively spreads to the occipital side, the outcome becomes the same irrespective of the PW position. Hence according to Park et al.,[16] the location of the PW gives an idea to the extent of superior margin of SDA and the authors had suggested that alopecia mostly progresses within 6cm of the PW toward the occipital side among their study group and 97.5% of the study group had their occipital fringe 4.5cm below the PW. This area below the occipital fringe was considered as SDA [Figure 2].[16]

Close

Figure 2

Landmarks for measurement of parietal whorl positionVM = vertical bimeatal line, PW = parietal whorl, OF = occipital fringe, HR = horizontal plane, which connects the upper border of the helical rim

Export to PPT

It is worth emphasizing that there can never be one valid, totally SDA for all patients. A family history, assessment of the future progression of the androgenetic alopecia, and clinical examination would be necessary to confirm the boundaries of SDA. One should always err on the side of caution. There is a paucity of literature regarding the SDA in Asians and particularly Indian population. More studies are required for assessing whether the same findings reported from the studies of Caucasians are applicable to other race and ethnic groups.

Should hairs be harvested from nonsafe area?: It has been argued of late by some hair transplant surgeons that hair from nonsafe area or less safe area can be harvested too, after appropriate consent from the patient that such hair may disappear in future, but patient will enjoy result for some time. These surgeons have likened this to the issue of other temporary results in treatments such as botulinum toxin, fillers, or surgery in vitiligo where relapse may occur. This approach is an offshoot of the development of FUE as the sole method of harvesting and the demand for larger sessions. As will be clear in the next discussion of FUT versus FUE, there is an ethical and mathematical upper limit for the number of grafts that can be harvested by FUE, of approximately 2500 in one session. Any requirement for more than this number can only be harvested either by accessing the nonsafe area in scalp or from a different part of the body. As body hair has its own limitations, it is tempting for the surgeon (or more likely the technician) to harvest from the scalp, particularly in a gullible patient who is desperate to have as many hairs as possible. In our opinion, this argument is untenable and only permanent hair should be used as a graft. It is entirely unethical to market HT as the only permanent method of hair restoration and then harvest from the nonsafe area, even if the patient consents for the same. The patient, already under stress of baldness, is gullible and easy to misguide. Harvesting nonsafe hair, leading to future loss from the grafted area, would bring the technique into disrepute and should be avoided in all situations.

Summary: It is important that hair transplant surgeons understand the concept of SDA. The upper and lower limits for the donor should not be breached.

Donor scar: is the scarring less in FUE?

Strip harvesting produces a single linear scar. This is a significant concern for patients who wish to wear their hair very short. Although the thin linear scar is easily concealed by the hair above the scar, there are patients who have scars that have widened and there are also patients who have several scars from multiple procedures. Strip excision is a surgical technique that needs expertise and adherence to proper closure techniques. Of late, there has been influx of doctors of all specialties into this field, who may not have the necessary surgical skill. Patient’s healing tendencies vary and hence tendency to scar also varies. Aggressive harvesting to obtain large number of grafts, over 3000–3500 from strips over 2cm wide, leads to wide scars. Several techniques have been introduced to minimize the width of the strip scar such as limiting the width of the donor strip to less than 1.5cm, minimizing the tension while closing the wound, double-layered closure, undermining the edges, careful dissection along the line of incision to avoid damage to the follicles, including the previous strip scar and trichophytic closure, and insertion of few grafts into suture at the end of the surgery.[1718192021] Proper planning and execution greatly reduces the problems associated with scar formation in strip surgery. In spite of such meticulous procedure, some individuals end up with a bad scar.[22]

The primary rationale for the use of FUE is that a linear scar is avoided. FUE has been marketed as a technique that does not involve cutting and is therefore marketed as “nonsurgical” and “scarless”. Although a linear scar is not created with FUE, circular scars are created and hence it is not proper to use the terms scarless or no scar. The total area of excision is greater with FUE than with strip harvesting. This is apparent when one calculates the circumference of a 1-mm punch (1mm × π = 3.14mm) and then multiplies this by the number of grafts, for instance, 1000 grafts (1000×3.14 =3140mm, which equals 314cm). In comparison, in a strip harvest of 1000 grafts, assuming an average density of 80 FUs/cm² and a 1-cm strip width, the length of the scar created would be 12.5–37.5cm (12.5cm per 1mm width of the scar, presuming the scar width ranges 1–3mm). Hence, the accumulated scarring area of FUE is greater than the area of linear scaring in FUT.[23] If a patient becomes extensively bald (i.e., the donor fringe becomes very narrow), the line of FUT will generally still remain hidden, whereas the dots of FUE will be seen above (or below) the fringe of hair.

With each subsequent session, the scarring in FUE is additive. For example, if the first FUE session is 2000 grafts, there will be 2000 tiny round scars. With a second session of 2000 grafts, there will be a total of 4000 scars. In contrast, with FUT, the first scar is completely removed in the next procedure. Even though the scar may be longer in the next session, with FUT, regardless of the number of procedures, the patient is left with only one scar. The scarring and distortion of the donor scalp from FUE make subsequent FUE sessions more difficult.[21]

Quality of grafts: does FUE yield less viable grafts?

High-quality grafts are ones that are obtained from the most permanent part of the donor area, undamaged, and contain a protective layer of tissue around the follicles. The protective dermis reduces mechanical injury during insertion and from drying when the grafts are outside the body. FUT typically yields high-quality grafts, especially when clinical assistants are extensively trained in stereomicroscopic dissection.

Some FUE grafts have very little tissue surrounding the follicles and are more prone to dehydration and damage because of manipulation during insertion of grafts, which might lead to reduced survival of the grafts in FUE.[23] The lack of perifollicular tissue is often a result of “pulling” on the graft to remove it in FUE. No adequate studies are available to compare survival rates of grafts between FUT and FUE. In spite of the disadvantages in the FUE grafts, excellent results have been documented by FUE surgeons worldwide.

Transection rates: is transection rate higher in FUE?

One-off repeated aspect of FUE is that it leads to higher transection rate. FUE is a blind procedure in contrast to FUT. Strip, which is an open procedure with dissection, is performed under stereomicroscopic dissection. FUE involves releasing the hold of arrectores; however, the level of attachment of arrectores cannot be visualized. It is this fact, coupled with the pyramidal shape of the unit (with splaying of hairs at lower end) that results in transection. Partial transection decreases the total number of hairs in the graft and thus reduces the overall yield. Completely transected hairs do not grow. Hence, there is a need to reduce the transaction rate in FUE to as minimum as possible.[21] In those individuals who had underwent mega sessions of FUE earlier, the transaction rate is greater in subsequent sessions because of angulation and scarring created during the previous surgery.[21]

However, it is also true that FUE techniques and instrumentation have improved over the years, transection rates have fallen from a high of around 10%–20% few years back to 2%–5% now. The time for extraction has also come down with better instrumentation, and it is now possible to complete a 3000-graft session in approximately 8h in 1 day. All these have resulted in increased popularity of the technique.

Using optimal donor hair: which method yields greater number of grafts?

Another difference between FUT and FUE is the proportion of FUs that can be harvested from the SDA. As discussed earlier, FUs at the outer edges of the donor area are more likely to be lost over time because of the progression of the balding process, but those from the midportion of the donor area tend to be more resistant to balding.

In FUT, the donor strip is removed from the midportion of the permanent zone, and there is a limitation to the width that can be safely harvested. In FUE, the surgeon is only able to harvest about one of every five follicles in a given area or 20% (this compares with 100% using FUT/strip).[2324]

However, in contrast to the above facts, there is one aspect where FUE is superior—FUE is the only method to extract body hair. This offsets the above limitation for the number of grafts from scalp.

Technical expertise: is FUE easier?

FUT needs greater surgical skill for proper closure and microscopic dissection. The surgical skill required to master FUE is different from FUT. In FUE, which is a blind procedure, surgeon should be able to align the punch to the angle of the follicles, presume the depth of the incision, and avoid transection.[25] Patients with curly or very wavy hair may be difficult to treat when FUE is used. In comparison, strip harvesting is suitable for all types of hair. FUE can be a tedious process and both patient and physician may experience fatigue. This can limit the amount of grafts that can be harvested in a single session.[25] The physician may need to use high power loupes 4×–6×. Working at a shorter focal distance can be tiresome and lead to neck problems.[25]

Complications: is FUE safer?

Specific features that promote FUE are lesser postoperative downtime, faster healing of the donor area, and rapid recovery, and there is no doubt that FUE leads to smoother postoperative period. Chances of hypertrophic scarring and keloids are rare in FUE. However, some complications, though minor, can occur in FUE such as burying of grafts, pinpoint white scars in donor area, and moth-eaten appearance in donor area because of over harvesting, epithelial cysts, donor site infection, and necrosis of donor area.[26] In contrast, FUT is associated with significant postoperative pain, hypertrophic scars, folliculitis, cyst formation, and so on.

Team and setup

Strip harvesting requires a larger staff, larger theater, stereomicroscopes, and larger space than FUE. For FUE, the surgeon can organize the surgery with just one or two assistants. For beginning surgeons, this is a major disadvantage as FUE also needs less stringent theater requirements.[27] In FUT, technicians have to be taught how to dissect under microscope, which can be time-consuming. In contrast, there is hardly any dissection involved in FUE.

Summary: Strip harvesting and FUE are both acceptable techniques for harvesting donor grafts. Each technique has advantages and disadvantages. Combining FUT and FUE improves the graft outcome and the yield. FUT scores higher when multiple sessions of HT are required for a candidate and to have maximum optimization of the grafts from SDA. FUE is well suited for patients who insist on not having a linear scar. It may be an excellent choice for young patients seeking small procedures. FUE is the only choice for harvesting trunk, leg, and arm hair, and it is an excellent way to camouflage strip scars. However, the simplicity of the technique has also meant that unqualified people (technicians) have started performing this procedure independently, without supervision of surgeons. This aspect is discussed in the next section. Surgeons should learn all types of surgery and use the technique for each patient as per his requirements. Table 1 summarizes the comparison of the two techniques.

International Society of Hair Restoration Surgery position statement on qualifications for scalp surgery

The position statement of the international society of hair restoration surgery (ISHRS)[28] is that any procedure that involves tissue removal from the scalp or body, by any means, must be performed by a licensed physician in the field of medicine (adopted by the Board of Governors ISHRS, November 15, 2014). Physicians who perform hair restoration surgery must possess the education, training, and current competency in the field of hair restoration surgery. It is beyond the scope of practice for non-licensed personnel to perform surgery. Surgical removal of tissue by non-licensed medical personnel may be considered practicing medicine without a license by state, federal, or local governing boards of medicine. The society supports the scope of practice of medicine as defined by a physician’s state, country, or local legally governing board of medicine. In fact, it is for these reasons that ISHRS changed the nomenclature of “follicular extraction” to “follicular unit excision” and defined “follicular unit excision” as consisting of two procedures: incision and extraction.

Position statements by AHRS India

The internationally accepted guidelines, which are also endorsed by associatioin of hair restoration surgeons (AHRS)-India,[29] regarding role definition of a hair transplant surgeon, state that the following aspects of hair restoration surgery should only be performed by a qualified hair transplant surgeon:

• Preoperative diagnostic evaluation and consultation

• Surgery planning

• Surgery execution including:

  • Donor hair harvesting

  • Hairline design

  • Recipient site creation

• Management of other patient medical issues and possible adverse reactions

• Postoperative care

AHRS-India in October 2015 has resolved that the only specialties eligible to become members of AHRS-India would be

• The master of plastic surgery

• Doctor of medicine or postgraduate in dermatology

• Master of surgery (MS) or postgraduate in ear nose throat surgery

• MS general surgery

We believe that technicians should not perform any aspect of surgery independently; they should perform only under supervision of a physician and they are allowed to perform only those steps, which do not involve incision of the body. Hence, they should not perform scoring (incision), slit making, and suturing. They can be involved in picking up the grafts (extraction) after scoring, implantation into premade slits, arranging the grafts, and placing the postoperative dressings.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.