By definition a Revision is a procedure that sets right an imperfectly done earlier procedure.
The imperfection can be due to the following reasons:
1. A doll’s head look due to punch grafting of yester-years when large size punches were used and they gave an ugly appearance Ken would not want on Barbie!
2. In contemporary times, a hair transplant done by a novice surgeon/ technician without adequate training. This could have led to any or all of the following which may need correction-
(a) Placing 2s and 3s in the leading row of the hairline
(b) Placing grafts deep leading to pitting and puckering
(c) A wide and ugly FUT scar that cannot be hidden with native hair
(d) A hairline that is too low or assymetric
(e) Temple points may have been sited unnaturally
(f) Poor growth of planted grafts
(g) Mal-directed slits resulting in hair growing in a wrong direction
(h) Planting body hair in areas where they look unnatural. eg. Filling the crown area with beard hair which are bound to look unnatural.
The reason we are suddenly seeing a rash of badly done hair transplants is due to the sudden rise in popularity of FUE hair transplants and its unethical promotion by companies selling FUE hair transplant systems. The gullible young and veteran surgeons get the impression that the machine will do all the work and that it is a wise addition to one’s present plastic surgery/ dermatology practice to earn extra revenue at times when there is a slump in the cosmetic enhancement market.
In certain countries like Turkey and India where most clinics employ fly by night technicians for the complete process of hair transplant, there is no sense of responsibility to the procedure or the patient. Since the doctor is not a part of the procedure there is no quality control. The largest revision case inventory is in these countries.
The commonest causes of poor results can be enlisted as under-
1. Donor Overharvesting
The safe donor area typically contains one fifth of the total hair in the normal scalp (20,000 follicular units or grafts). The FUE surgeon must view the donor region as a critical bank of a fixed number of reserve hair follicles for transplantation. The follicles are a precious finite commodity and any apathy as regards the transection rate is to be condoned. Another very important concept for the beginner or intermediate FUE surgeon is the exact number of grafts harvested over a lifetime will vary from one patient to another. Clinical experience dictates how many grafts can be trasplanted in an individual patient. There is no study or documentation in medical literature giving hair surgeons guidelines to follow. A general rule is when the patient’s scalp is seen through thinning hairline and/or the patient’s donor region follicular density is cosmetically unappealing, future donor harvesting may be limited. Obviously, harvesting adjacent follicles will result in a donor scar similar to the donor linear scar produced. If concerned by possible overharvesting, one should incorporate body hair grafts into your practice to meet the shortfall in scalp grafts.
2. Visible Scarring
FUE has been mischaracterized as a scarless technique. In fact, there is a possibility, especially in darker skin types, to develop small areas of hypopigmentation in the donor region corresponding to the previously removed graft. It is believed by the FUE academic community that the lack of melanin resulting from the previously harvested follicle is the reason we observe small areas of hypopigmentation. (Figs 5A-E)
Visible scarring can occur in the following instances:
(a) FUE harvesting systems are of variable quality. Cheaper systems with high torque can cause significant frictional heat generation that can lead to burning of the epidermal edges of cored skin resulting in bigger scars.
(b) If punches are too close, the slender bridge of skin holding 2 circular incisions apart breaks down due to necrosis, resulting in coalescence of adjacent holes. For example, two 0.9 mm holes will create around a 2.0 cm wide scar, which is visible to the naked eye.
(c) Another way to produce more visible scarring is by creating an oval-shaped incision that would result in a scar that occupies a larger surface than a round incision. When hair angles are acute, instead of aligning the punch to the skin surface, the punch takes along more skin in the direction of the follicle, leaving behind a larger footprint thereby causing an oval-shaped incision and a longer linear scar. This happens when harvesting low down along the nape of the neck, harvesting beard hair along upper neck and chest hair above an imaginary horizontal line running through the manubrio-sternal junction.
(d) Abrupt transition between harvested and non-harvested areas can lead to a visible scar. It can also occur when a large number of grafts are taken in the “unshaven” or “micro-strip” technique. Therefore, it is important that the transition line not be abrupt and that the transition areas along the superior and inferior edges of the safe zone be feathered to give a softer look.
In order to improve your technique, consider the following:
(a) Punches should be chosen for donor harvesting based on the size of the follicular grouping and not arbitrarily.
(b) Invest in a good quality harvesting system. A good system has the following characteristics
(i) It is simple.
(ii) It requires infrequent and economically viable maintenance.
(iii) Repair should be simple and parts easily available.
(iv) It should be affordable so a spare system can be kept for contingencies.
(c) Always keep one follicular unit between harvest sites. This will give a harvesting ratio of not more than 1:5 and will prevent overharvesting which leads to visible scarring.
(d) Application of a cephalad force to the donor harvesting area with the non-dominant hand will decrease the acute angle of entry by the punch and subsequently leave a smaller wound surface area
3. Transgressing the “Safe” Zone
The permanent or safe donor zone from where FUE harvesting is performed is defined by the following 4 imaginary lines:
(a) A horizontal line 3 cm above the superior pole of the pinna
(b) A vertical line through the tragus of either pinna
(c) The nape of the neck-is the area 2.5 cm inferior to the occipital protuberance where the skull is masked on palpation by overlying muscles.
(The illustration is attached)
The confines of the donor area are not sacrosanct as have been seen in some cases of extensive balding. Clinical judgement in anticipating future areas of balding takes precedence over scalp geometry. Violating the confines of the permanent zone will lead to hair shedding in the long term with loss of density in the transplanted area. Also, harvesting outside this safe region can lead to visible scarring, as the rim of the balding crown expands caudal to expose the harvested area. The lower edge of the safe zone can also get exposed in rare cases of reverse alopecia.
4. Graft Damage and Suboptimal Growth
Though FUE and FUT are two distinct and separate harvesting techniques, theoretically there should not be any difference between the two in respect to the end cosmetic results. However, the very nature of the FUE technique and the instruments used may cause damage to the grafts and thereby suboptimal growth. Though smaller dissection punches are preferable as they create smaller lesser than 1.0 mm diameter dots of donor hypo-pigmentation scars, they also may cause more transection and harvest grafts that are skeletonized which are prone to dessication and trauma. In addition, high speed, high torque of any drill system used for FUE may have a wringing effect on the hair follicle. This can be traumatic and can lead to poor growth. Quality harvesting systems like the SAFE Scribe™, PCID system, etc. are engineered for use in delicate hair restoration surgery unlike the dental drills used by many surgeons in developing countries. (Fig S 3A-B)
Use of the “blunt” punch considerably decreases the transection rates in my practice. With experience garnered over time, I have realised a 0.8-mm blunt punch works well for Caucasians and some selected East Asian follicular units. The 0.9-mm blunt punch works well for all other racial groups. However, clinical judgement and discretion weighs supreme in selecting the right punch for the individual patient.
Optimal magnification: I use the Carl Zeiss 4x head mounted loupe which is ideal for working long hours since the weight is distributed circumferentially around the head rather than on the bridge of the nose.
If you believe that FUE is the oldest surgical hair restoration procedure, we have come full circle. Gone is the era that associated punch grafting with bad pluggy, doll’s head results. Today’s FUE is a refined procedure that relies on miniscule punches, which range in size from 0.65-0.85 mm to provide an undetectable, natural result with high density without leaving a visible linear scar.
The large number of doctors jumping onto the ‘FUE bandwagon’ with very little learning is however alarming. Hair transplant is seen as a multi-billion dollar industry and at times attracts the wrong talent. Aggressive marketing and the field of medicine often make for strange bedfellows as can be seen in the accompanying images. The educated but gullible patient was sold a “test-grafting session” of 100 grafts, which were placed in an area that would be socially unacceptable and the patient would soon be forced to go in for the full procedure. In the second illustrative case the patient who could not immediately afford more grafts than were given to him was intentionally given a straight posterior hairline to make it look unnatural so as to facilitate and hasten his return to the clinic for a natural look, sooner than later. Recognizing that bad reputation travels farther than good reputation, one should resist using “selling” techniques but focus on practicing medicine. The Hippocratic oath binds us firstly not to commit harm to our patients.