Follicular Unit Extraction (FUE) is a method of obtaining donor hair for Follicular Unit Transplantation (FUT), where individual follicular units are harvested directly from the donor area, without the need for a linear incision. In this hair restoration procedure, a 1-mm or smaller punch is used to make a small circular incision in the skin around the upper part of the follicular unit, which is then extracted directly from the scalp.
FUE represents the fastest growing segment of hair restoration surgical specialty.
At the same time a significant amount of controversy has been seen pertaining to ethics, techniques, mechanization, quality of outcomes, patient candidacy and surgeon capability with respect to FUE.
The advantages of this type of donor harvest are that there are no stitches/sutures, no linear scar in the donor area, a minimal level of post-operative pain and the ability of the patient to resume active physical lifestyle two weeks after the procedure. Affected by widespread influence of media and web representation of hair restoration, most patients seeking surgical hair restoration fall in the one of three profiles
- Patients seeking only FUE as a preferred technique of donor harvest.
- Patients wanting to know which is the best form of donor harvest for them (they ask for your recommendation)
- A small subset of patients asking for strip harvest as the preferred mode of donor harvest
Common reasons for preferring FUE as the donor harvest
- No scar, No pain – is the most common answer
- Absence of linear scar
- Believe it is a more advanced technique (and strip harvest is a dated procedure)
- The biggest motivator for patients to choose FUE as a mode of donor follicle harvest is pictures of poor results of strip harvest or videos showing strip surgery which appear morbid.
Myths associated with FUE
FUE allows patients to have hair transplantation without the necessity of a linear scar in the donor area (as seen with conventional strip harvest). Several proponents of FUE market the procedure as a technique that does not involve cutting, is less invasive and does not result in scars (i.e., “scarless”). This however does not mean that there is no scar. The extraction sites leave behind small circular/punctate scars and hairless gaps which are visible when the hair has been cut short or shaved. These “dots” may be a scar reaction or actual post inflammatory pigment changes, particularly in darker skinned individuals. Also the human eye may pick up “spaces” where follicular units are missing in the normal pattern. Overzealous harvesting or use of significantly large punches can give a moth eaten appearance to the donor area (back and sides of the head). Also read www.ishrs.org/article/consumer-alert.
Inappropriate, Misleading, Inaccurate Terminology associated with FUE
- “Scarless surgery”
- “No incision”
- “No touch”
- “No cutting”
- “Hair multiplication”
- “Eliminates the need for additional procedures”
- “Pain free”
While a linear scar is not created with FUE, circular scars are created. The length of incision is greater with FUE than with strip harvesting. This is apparent when one calculates the circumference of a 1mm punch (1mm x pi = 3.14) and then multiplies this by the number of grafts, for instance, 1000 grafts (1000×3.14 =3140mm which equals 31.4cm). In comparison, a strip harvest of 1000 grafts assuming an average density of 80 FUs per sq. cm and a 1cm strip width the length of the scar created would be 12.5cm (1000/80 = 12.5).
The FUE is definitely less invasive as the depth of the incisions with FUE is usually shallower as compared to strip harvesting. The punch depth is to the level of the fat or at the fat-dermis junction. With strip harvesting the depth of incision is into the fat.The FUE procedure is usually more time consuming than FUT. An FUE surgery time varies according to the surgeons experience, speed in harvesting and patient characteristics. The procedure can take anywhere from a couple hours to extract 200 grafts for a scar correction to a surgery over two consecutive days for a large session of 2,500 to 3,000 grafts.
Eligibility for FUE
Usually patients eligible for strip harvest are eligible for FUE and vice versa.The patients who are ideal for FUE are:
- Young male patients who wear their hair very short or repeatedly shave their heads
- Minimum to moderate hair loss
- Pain sensitive patients
- Patients not desiring a linear scar in the donor area
- Poor donor density
- Prone to hypertrophic scarring
- When non scalp harvest is required (beard, body)
- Tight scalp
- Sportsperson (who wants to resume active physical lifestyle earlier)
There are many types of punches and ways to use them (manual punches, motorized punches, sharp, blunt, among others) and all of them can offer good hair transplant results in experienced hands. What makes a big difference is the surgeon’s ability and experience. There is even a robot which helps the surgeon in the extraction process of the FUE. Punches can be sharp or blunt and both work well.
The punch size choice is a delicate balance between the number of hair desired from the donor harvest versus the scarring in the donor area. The most common sizes of punches used at our clinic are between 0.8 mm to 1.0 mm diameter.
The size of the punches used is determined by the following factors:
- Hair shaft caliber (the larger the caliber – larger is the diameter of the punch)
- Density in the donor area (number of follicular units per unit area and number of hair per follicular unit) – More number of hair in a follicular unit larger is the punch diameter
- Curl of the hair – Curly hair may need a larger diameter of punch
- Grade of hair loss ( More is required and hence a larger sized punch can yield more hair per graft)
Preoperative planning and preparation in FUE
This is similar to that in the strip harvest. Pre-operatively, patients should discontinue minoxidil to reduce the risk of bleeding and abstain from alcohol, smoking, and non-steroidal anti-inflammatory drugs (NSAIDs) for seven to ten days.
The hair in the donor area is shaved to 1-2mm in length to allow adequate visualization of the direction of hair entry into the scalp and direction of the hair bulb. The donor area can be fully shaved (if the plan is to extract more than 1200 grafts), or “micro shaved” into 3-5mm strips for patients who wish for a less noticeable donor area (who need less number of grafts). There are some centers which perform non shaven FUE where the donor area is not shaved at all. It can be done in selected cases but is fraught with higher transection rates.
The patient is placed in a prone position (face down) for harvest from the back of the head, or on one side for harvesting from the sides. Sometimes the extraction may be performed with the patient sitting up. We find that the patient lying face down gives us better control over the process and helps in reducing transection rates.
The anesthesia is the same as that for the strip harvest. We use magnification for the extraction. Grafts are largely taken from the back of the head because these hair follicles belong to the safe donor area (SDA). Hair on the sides behind and above the ears is thinner and can be used to create a more natural look in areas with normally thinner hair growth, but these hairs when grafted experience a greater degree of thinning over time.Punch size is chosen based on the factors mentioned above. The commonest punch size we use is 0.9 or 0.8 mm. The punch device is aligned over the scalp in the direction of the hair bulb and advanced to the level of the lower dermis. The trick to avoid transection of the follicle is to centralize the punch accurately over the follicular unit.
A unique set of challenges exists with all FUE methods. First and foremost is that FUE is a blind procedure. The most important aspect of harvesting hair directly from the scalp using a punch is that it needs to precisely follow the direction of the hair follicles in order not to damage them. The exit angle of the hair as it emerges from the scalp changes as it does so. The operating surgeon has to presume that the follicle below will follow the same angle approximately as he cannot see it directly and this is the blind aspect of FUE. More significantly the hairs as they exit from the scalp are sitting in a tight bundle but the parts below can spread out or splay. The splaying occurs deeper and hence it is important to restrict the depth of penetration of the punch especially if one is using a sharp punch.
The downside of limiting the depth of the punch is that more force is required to extract the graft after coring it, as there could be fibrous connections which could be holding the follicles down.The principle behind Follicular Unit Extraction (FUE) is that, follicular units would not be totally excised (cut) from the scalp, but rather “extracted” or pulled out of the scalp, so that the lower part of the follicles would not be cut off.In spite of centralizing and directing the punch accurately over the follicular unit, the very act of pulling the graft (extraction) can denude the lower portions of the follicles of the soft tissue coverleaving the lower part of the follicle “nude”making it susceptible to injury and drying leading to poor growth.
This is still a major stumbling block and challenge for surgeons using FUE.
As the extracted graft leaves behind a spot which is hairless the surgeon needs to leave behind 4 to 5 follicular units around it to cover the spot. In short, one is able to harvest about 20-25% of all the follicles in a unit area (this compares with 100% using FUT/Strip). So, a larger donor area is required to achieve the same yield. Many a times because of this the surgeon ends up harvesting follicles from outside the safe donor area and by doing so the quality and life span of the implanted hair is poor.
In order to avoid this but to get the necessary number of grafts, the surgeon may overharvest from the safe donor zone leading to a visibly thinned out area or a moth eaten appearance of the donor area.We, at Hairrevive have seen a significant number of these cases. These surgeries were seen to have been primarily performed by untrained doctors or technicians.
Extracted grafts are then kept in storage solution until ready for transplant. After the surgeon has punched an area of donor scalp, the assistant removes the follicles while the surgeon moves to another area to expedite the harvest process.
Post-operative care includes placement of compression or a simple sterile bandage on the donor area. The recipient area is left open for regular saline sprays. Massage and ice compresses on the forehead may be used as needed for swelling expected about three days after the procedure. Healing occurs by secondary intention and re-epithelialization of the donor area is complete two to three days after FUE. New hair growth in recipient area is seen in about the third to fourth month post-operatively.
Sometimes small boils or pustules are seen in the transplanted areaand these are benign and do not usually impact the hair growth.
Healing and recovery in FUE
The postoperative recovery of the recipient area is similar to that of strip harvest but the donor area recovery is much faster in FUE. Presuming that scalp hair grows at the rate of 1 cm a month, the hair in the donor area (one that is not extracted) would be about 3-4 mm long. This would be adequate to start covering the donor sites. Moreover as there are no sutures to be removed the patient can resume active physical life after two weeks.
Potential complications of FUE
FUE is a minimally invasive method of donor follicle harvesting but it has its share of potential complications. Below are some of the complications which are unique to FUE
- Being a procedure that is essentially blind there is a potential for graft transection. It essentially means visible breakage of the follicle anywhere along its length. Transection could be complete when all the hairs in the graft are cut transversely or partial when only one is cut and rest of the follicles are intact. The key to successful FUE surgery is avoidance of transection. It is possible for the transected graft to have some growth but the chances are slim.
- Stripping of the critical growth centers of the hairs within the graft during the extraction process known as desheathing or paring.
- Buried grafts (grafts that are pushed below the skin becoming foreign bodies with potential cyst formation or even abscesses producing possible infections in some patients).
- Over harvesting
- Harvesting outside the permanent donor zone.
- Temporary altered sensations in the donor area.