Follicular Unit Micrografting With Extraction (FUE)
Follicular unit extraction (FUE) is one of the techniques for obtaining donor hair for hair transplantation. FUE removes one FU (Follicular Unit) at a time, by excising from the scalp using a small, sharp cylindrical punch (generally 0.8mm to 1.0mm in diameter). The punch incises the skin surface around each hair follicle before they are carefully teased out manually with forceps.
At Hairrevive, we choose the procedure ideally suited to a particular patient depending upon his grade of hair loss, pattern of hair loss, age of patient, donor area density and the patient's hairstyle. FUE Technique is a good option for those with early grade of hair loss, are young, keep their hair shortand have an abundant donor area.More advanced hair loss like Norwood Grade 4 can be treated with FUE but the person has to have better than average donor hair densityand good hair characteristics to ensure sufficient FU numbers can be safely extracted and not cause thinning of the donor area andleave options for the future.Also patients who do not want to have linear scars at any time and patients with poor scalp laxity who may have excess tension upon closure after a strip harvest (this problem is usually more pronounced after multiple strip harvest excisions) may also be candidates for FUE.
Another indication for FUE is for eyebrow, moustache and beard augmentation/restoration where one can select fine hairs for transplantation.
Safe donor area
(Grade VII hair loss showing the
permanent zone of hair)
If you see a man with severe balding, the existing hair represents the limits and confines of the donor area. This is the hair zone that is considered permanent. With rare exceptions, this rim of hair remains even in the most advanced cases of male pattern baldness.
One of the assumptions made while planning any hair restoration procedure is that any man considering hair transplant surgery will eventually progress to this advanced level of balding. Visible scars may be revealed if the baldness advances or donor tissue has been taken too high, too low, or too far in front of the ears.
The objective in hair transplantation is to use only hairs that are destined to remain permanently in their original site. The concept of safe donor area is largely attributed to Dr Walter Unger who was able to outline a zone containing the hair follicles that were the most likely to be relatively permanent. This quantitative model of a safe donor area serves as the fundamental foundation in hair follicle harvesting for follicular unit transplantation (FUT), whether the grafts are being obtained via strip harvesting or via Follicular Unit Extraction (FUE). Harvesting hair follicles for transplantation from regions of the scalp lying outside the borders of the safe donor area poses two increased risks: 1) only temporary survival of the transplanted follicles, and 2) Subsequent donor scar exposure if the follicles have been removed from a region of eventual substantial or total hair loss.
Donor area in FUE
In contrast to the strip technique, in Follicular Unit Extraction (FUE), a larger area of the donor scalp needs to be trimmed. The reason for this is that, small open holes are left after the grafts are removed. In order to cover these resultant scars a substantial amount of the donor hair in this area must be left behind. Roughly, to hide the small scars caused by one unit being extracted, one has to leave the surrounding five to six follicular units (depending upon donor density and donor hair calibre) intact to conceal the scar. As a result of this one needs a larger donor area to get the same number of grafts. This will include the entire back and sides of the scalp in large sessions (>1000 grafts) and a long, thin band in smaller (up to 500 grafts) procedures. A FUE session of 1000 to 1500 FU spaced every 4th to 5th FU apart, generally can be managed in within the permanent safe donor area. But larger sessions above 2500 grafts to 4000 grafts would require harvesting from non-permanent donor/scalp area.
Harvesting FUs from a larger area (as compared to Strip/FUT) does not imply that we can get more FUs. It is important to remember that from the given safe zone one can harvest only 25% of hair follicles without causing an obvious thinning. By that token if the average donor density is 75 FU/sq.cm and the area is approximately 150 sq cm (6 cm X 25 cm) - the total number of FUs present are 150 X 75 = 11250. The total number of FUs that can be harvested by FUE is 25% of 11250 = 2812. This is the maximum number of grafts you can harvest without thinning out the donor area or creating a see through effect. Also it is important to keep future hair loss in mind before utilizing all of this in one session because once we have harvested a large number of grafts by FUE; a second session will definitely expose the scars and create a see through effect.
On the other hand in the strip harvest if one harvests anaverage strip of 25 X 1.25 cm (31.25)the total number of grafts harvested at one time would be 31.25 X 75 =2343 FUs. For a person with normal scalp laxity, a similar strip can be harvested again (remaining well within the safe area) at a later date yielding a similar number of grafts.All this, while leaving behind a single linear scar which stays in the permanent zone of donor area and will rarely be visible, even with advanced grade of hair loss.
Scars in FUE
The primary rationale for the use of FUE is that a linear scar is avoided. 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"). 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 (1000x3.14 =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).
Pre transplant preparation
You will arrive at the centre at 8 am after having had a light breakfast at 6 am and nothing taken orally after that. You would have taken the medications prescribed and shampooed your scalp with the medicated shampoo as prescribed.
You will be asked to change into the OR clothes. You will be given a head wash with an antiseptic shampoo. Dr Sattur will go over the proposed plan of the procedure, mark the hair line and the area to transplanted. This is done according to mutually agreed plan.
The hair in the area to be removed is clipped short, to a length of approximately 1-mm.
This is practically the same as that used in the strip harvest except when doing a larger number of grafts where one may have to anesthetize a slightly larger area.
Dr Sattur uses the sharp punches with internal diameter of 0.8 mm, 0.9 mm and 1.0 mm. If smaller punches are used, there is a higher rate of transection especially because Indian hair is coarser than Caucasian hair. The punches can be used with manual devices or mechanized devices.
0.8 and 0.9 mm punches
The manual punch-a circular hollow scalpel with a diameter of 0.8 to 1.0 millimeter-is the original FUE instrument.The punch is placed over the visible portion of a follicular unit's hairs, and pressed downward with manual rotation to incise the skin around the FU and free it from surrounding tissue. The FU is then extracted by traction with forceps. If the procedure is successful, an anatomically complete FU is made available for transplantation. The unanticipated complication of transection can damage one or more follicles in the FU in the process or incising or extracting.
The same punches can be mounted on a motorized device which rotates and helps reduce the force required to insert the punch. The aim of motorized punches is to make the procedure faster, less physically demanding, and safer in terms of decreasing potential for FU transection.
A FUE session to obtain enough FUs for transplantation can require several hours of close and careful work by Dr Sattur. A FUE session using manual instruments may harvest fewer than half of the follicles obtained by strip harvesting in the same amount of time.
FUE Grafts without trimming
FUE Grafts after trimming
A problem for FUE from its beginning has been the transection of follicles during the FUE procedure. The commonest way a hair follicle is damaged is by slicing or tearing it at a cross-sectional angle this is known as transection of the follicle. Transection occurs when the circular sharp blade of the hollow FUE punch fails to completely enclose the FU, and slices off a part of it. Transection can also occur when the FU is pulled apart when it is gripped and pulled with forceps. The damaged follicle(s) in the FU may be useless for transplantation, or fail to thrive if transplanted.
(Follicular transectionin FUE grafts)
Some confounding issues of FUE are inherent to the patient-e.g., follicles that take an unforeseen direction under the skin, so a punch aligned with visible hair above the skin makes an inadvertent cut into invisible follicles. Some issues are inherent to the physician-e.g., lack of skill and/or experience.
Grafts in FUE
Debate exists as to the rate of survival regarding FUE versus strip grafts. There is some concern that because the FUE grafts may have very little tissue surrounding them that they are less likely to survive. Such grafts are more prone to dehydration, which has been shown to be a major cause of diminished graft survival.
(Lack of tissue around the lower part of the FUE grafts)
The lack of perifollicular tissue is often a result of "pulling" on the graft to remove it. Because there is added manipulation in trying to remove a graft this may also contribute to diminished survival. Sometimes the ends of the bulbs are splayed or unusually far apart. This makes the bulbs more susceptible to trauma, as a result of increased graft manipulation during implantation. As of this time there are not adequate studies to compare survival rates.
The implantation process is the same as that of the strip technique except that the grafts from FUE have less tissue surrounding the bulb and have to be handled more gently. These grafts are delicate can be damaged with even little bit of dryness as compared to the more robust grafts obtained by strip harvest.
Post - Operative Care
On the first day expect some soreness and possibly some numbness. By 2nd to 3rd day some scabbing is present as well as moderate redness. Soreness in the donor and recipient areas should be gone. Some numbness may continue. In about 5-6 days there will be some residual crusting. By 10 days patients can return to normal showering and the area appears normal other than the closely cropped hair.
Problems with FUE
When using FUE it is important to recognize that as more and more grafts are harvested the area may appear moth eaten. If grafts are taken too close together there may be an appearance of a scar. In some patients as large numbers of grafts are removed there can be a clear demarcation between the areas that have been harvested and areas left alone. This is opposed to the strip technique where hair of similar density is brought back together at the suture line. Opponents of strip harvesting would note that if hair does not grow well in a strip scar and the scar widens, then the scar might be apparent if the hair above it is short or otherwise thin.
(Over harvesting from an area can lead to see through effect)
Some of the surgeons who prefer FUE feel that patients experience less pain and there is a shorter recovery time. There is little data to support this view. One would need to compare the pain associated with comparable numbers of grafts harvested per session. For instance one would want to compare, for example, 1000 grafts harvested with strip vs. the same number harvested with the FUE technique. The fact that pain is very subjective complicates such studies.
Patients may complain of altered sensation but this can occur with strip harvesting or FUE as small nerves are cut in both procedures. Years ago some strip-harvested patients may have experienced significant dysesthesia as a result of damaging the occipital nerves. As dissection should be at the level of the fat or perhaps at the level of the fascia these nerves should not be damaged.
Bleeding occurs with both techniques but more significant bleeding occurs with strip harvesting. That said, bleeding is not considered a problem with strip harvesting and in most cases bleeding is nominal.
A complication that is specific to FUE harvesting is the burying of grafts. This happens when the punch pushes the graft into the subcutaneous tissue. The grafts can be difficult to recover and can lead to a foreign body reaction and cyst formation.
Mandatory to shave the scalp
In general hair must be cut short to be harvested with FUE. At times layers can be created allowing hair to cover the harvested areas but this places a limit on the amount of hair that can be removed at the session.
To perform a proper FUE session, the donor area needs to be shaved totally, except possibly for small procedures such as 100-500 grafts when smaller areas could be shaved and hidden by surrounding hair. Shaving will allowing the doctor to precisely measure the angle the FU exits the scalp as well as give a greater comprehension to the position within the skin, a very important aspect of the extraction.
If there is need for anything more than 500-700 grafts then a formal shaving of the donor area is required. This places the patient in a peculiar position with respect to his/her social and professional situations in the post-operative period.
The recent promotion of mechanical devices and powered follicular extraction devices has sparked renewed interest and controversy regarding this method of harvesting. A great deal of discussion by physicians, ancillary personnel, and the general public has occurred on the Internet and multiple media sources about the value of FUE versus strip harvesting and vice versa. Sadly, many of the claims of "superiority" of the newer technique seem more related to marketing and self-promotion rather than a clear scientific evaluation.