FUE Angulation
Dr. Alan Feller

Angulation

Patient position

To maximize success, the patient should be placed in the prone position on the table. His head should be flexed down to expose the occipital area and to angle the hairs as close to vertical as possible without causing discomfort to the patient

Picture of prone patient

Tumescence

After local anesthesia has been applied to the donor area, generous amounts of saline should be injected both sub Q and intradermally. This will make the skin rock hard and make the FU s stand up a bit more within the skin.

Before and after photo of teemed skin

Punch angle

While holding the punch in the dominant hand, note the angle of both the hair (which should be about 2mm long) and the mons folliculi which is the bump of the FU that sticks up from the skin. This will give a sense of the mass and direction of the FU in the dermis. Take the punch and slide it over the target FU being careful to keep the hair in the center of the punch. This is the crucial angle that can result in success or transection.

Depth Control

Scoring

Once the punch is at the proper angle and sitting on the epidermis, a reciprocating twisting motion should be initiated as pressure is applied. The goal is to cut through the epidermis into the shallow dermis which usually represents the first 2mm or so. It is best to pull out the punch at this point and inspect the FU under magnification to determine if the correct angle of attack has been achieved. Once satisfied, the punch is driven down another 2 or so millimeters until approximately 85% of the FU has been separated from the surrounding dermis and sub dermis. Do not bury the punch to the adipose layer as it may transect bulbs that tend to splay out in the deep dermal and adipose layers.

Also, as you continue down into the deeper dermis it is best to minimize the twisting motion as the lateral portions of the FU containing delicate follicles may get sheared off.

Picture of sheared off Follicles

This may happen because while the upper portions of the FU have been freed by the punch, the lower parts are still attached to the stationary scalp. Thus as the punch travels lower, more and more of the FU is contacted by the wall of the punch allowing for a greater and greater torsion force to act on the FU. The friction of the graft against the wall, coupled with rotation, creates a catastrophic shearing force that literally rips the outer follicles off the FU leaving what can be seen in the photo… an intact central follicle with partially transected lateral follicles.

While this phenomenon did happen in the old style large plug harvesting, it was largely ignored because the relative number of sheared follicles was inconsequential compared to the number of intact follicles. This loss was, of course, cumulative and once recognized by more exacting practitioners ultimately lead to the vilification and lasting stigma of that wasteful technique.

Delivery

Once Angulation and Depth Control have been properly applied, it is time for the Delivery phase, named as such to purposely conjure an image of child birth in the mind of the practitioner; for that is what it is most similar to, and should be treated as.

Remember, the depth control aspect freed up only 85 to 95 percent of the FU, leaving the other 5 to 15 percent of the FU still firmly attached to the deep dermis. To free the graft in its entirety, intact, a few more steps must be executed.

To Deliver the graft, the FU should be grasped firmly with fine forceps across the width of the FUE, well below the level of the epidermis.

Picutre of forceps grasping graft below epidermis

It is tempting to grab just below the epidermis as it seems to act like a natural flange preventing the graft from slipping out of the forceps, however, the epidermis’ attachment to the dermis is deceptively poor and will result in the tearing out of the epidermis by the forceps, and the retraction of the mutilated graft back into the scored hole from which it came.

Photo of retraction

Once the FU has been properly grasped by fine forceps, traction is applied evenly and gently along the axis of the graft. The doctor must adjust the angle and pressure during this maneuver in a mannor similar to the guiding of the new born during birth; and with as much delicacy and finesse. This is very much the ART portion of FUE and can only be appreciated through practice.

What is actually happening physiologically during delivery, is that the lower connections to the scalp are tearing away under guided traction. In many cases, the graft will simply “release” and the delivery will be complete, however, many times the graft simply will not come free, or worse, the traction force will cause the graft to rip in half, leaving the lower parts of the FU in the scalp, and the upper parts in the grip of the forceps.

Perforation

In order to avoid graft tearing, as opposed to connective tissue damage, it becomes necessary to employ just one more step termed perforation. Just as an episiotomy is sometimes required to deliver the child with the least amount of trauma, so must perforation be employed to deliver an intact follicular unit. While their roles are congruent, the mechanics of perforation are very different.

If a properly scored follicle simply will not deliver on its own when under traction, all the practitioner need do is continue the traction (don’t increase it as the hand will instinctively want to do), then take a 27 gauge needle in the non-ominant hand, slide it down between the partially delivered graft and the hole it is coming from, and drive it into the adipose layer. This will undermine the structural integrity of the holding tissue until the point of tearing is achieved. Usually, after 2 or 3 pokes or perforations, the graft will come free- intact.

The perforating procedure does not need to be visualized for two reasons: The first is that the chance of hitting a splayed bulb is very low to begin with considering the bulbs may exit in approximately 10 degrees of a 360 degree geometry.

Show drawing of geometry

Secondly, if the 27 gauge needle comes into the area of a follicle, it tends to push the follicle out of the way. Very rarely will the sharp point of the needle successfully hit a follicle, even if it is stuck right through the FU itself very little to no damage will occur.