Evolution of Hair Transplantation

Introduction

Hair transplantation has gone through a big revolution with the pioneers in this field[15]. To achieve a good cosmetic result in hair transplantation, a natural-looking hairline with adequate density shall be established. There are numerous modifications of defined techniques with each one explaining and suggesting verified solutions.

This note describes the available options in hair loss surgery and the concepts of non-surgical approaches, and an experience is shared with a few patients grafted via direct hair implantation (DHI) method. Moreover, to us, this is the only study demonstrating the opening of the nests with sliced razor blade just before the implantation of the hair follicles. Thus, the evolution with the future of hair transplantation is summarized as well. Moreover, this article focuses on the surgical techniques. The medical management of hair loss is out-of-scope

Methods

Between January and December 2014, hair transplantation was carried out in 207 patients. The patients with beard and/or moustache transplantation, multisession transplantations and female patients were excluded. The harvested grafts out of the scalp were also not evaluated.

All the procedures were carried out under local anesthesia. The hair was cut 1-2 mm in length. Micromotor system was used in the harvesting of the hair follicles This system consists of punches attached to the hand-piece of the micromotor system (1500-3000 rpm). Punches were chosen according to the diameter of the follicles ranging between 0.8 and 1.2 mm. Harvesting of the follicles was handled in supine position. With the aid of the sharp punch attached to the motorized system, the follicle was detached from the surrounding tissue (approximately 3-4 mm in depth=deep dermis layer). Later on, it is released manually with fine-curved microforceps produced for this purpose. Temporooccipital region was used as donor site.

The harvested grafts were aligned in Petri dishes with cooled saline (4 °C). A dressing is made with sterile saline coated gauze to the donor area and the patient was turned to the supine position.

In follicular unit extraction (FUE) technique, razor blade that was cut into pieces was used to open the nests in vertically-oriented fashion that are to be grafted . With this, we aimed to diminish the incarceration of the implanted follicles. However, in DHI technique, the grafts were loaded to the DHI pens with one charged staff for this purpose  . The implantation of the follicles was carried out in accordance with the natural hair angles by the author under loupe magnification

Hair transplantation is comprised of consecutive steps: planning, preparation, anesthesia, graft harvesting, secure of the harvested grafts, graft transplantation, and dre

Technique

While several surgical treatment options (plug grafts, scalp reductions, transposition flaps) have been used historically to treat androgenic alopecia, we outline the two most common techniques of HT based on the follicular unit-principle, namely the follicular unit transplantation (FUT) and the follicular unit excision (FUE)

FUT Donor Site Harvest 

  • The patient placement is in a prone position.
  • If not done already, the donor site hair is trimmed to 2 mm.
  • The calculated strip length is marked, and a local anesthetic is injected superficially into the dermis. A tumescent solution may be injected as well to increase anesthesia, hemostasis, and dermal turgor.
  • A beveled incision is made parallel to the exiting follicles, into but not beyond the subcutaneous tissue (about 4 to 5 mm in depth).
  • With lateral retraction around the periphery using sharp skin hooks, the donor strip gets dissected off the galea aponeurosis and occipital fascia which minimizes bleeding and sensory nerve damage. NOTE: cauterization should be used sparingly to decrease the risk of permanent FU damage.
  • The donor strip gets prepared by removing excess subcutaneous tissue, with care to leave 2 mm of fat beneath the FU to avoid damage to the follicle.
  • The strip is then dissected (usually by a technician) under magnification into vertical segments one FU thick.
  • Individual FUs are then isolated with further sharp strip dissection and placed immediately into a holding medium of chilled saline. NOTE: the FU is susceptible to desiccation in just a few minutes, which renders the graft unusable.
  • The donor strip is then closed either primarily or with a two-layer closure using sutures and/or staples per surgeon preference.
  • The patient transitions to a sitting position for recipient site preparation and graft implantation.

FUE Donor Site Harvest

  • The donor site is shaved to 2 mm to visualize the angle of the follicles.
  • The patient placement is in a prone position for ease of harvesting.
  • Local and tumescent anesthesia gets injected into the donor site.
  • If manual FUE is being performed, a sharp punch (diameter 0.8 to 1.2 mm) is oriented within the center of the hair follicle at the same angle and advanced in an oscillating motion to a depth of 4 mm or less to prevent transection.
  • The FU is removed using delicate forceps in an atraumatic fashion and placed either directly into the recipient site (after inspection of FU integrity) or a holding medium of chilled sterile saline.
  • The patient then gets transitioned to a sitting position in preparation for recipient site implantation.
  • NOTE: Modifications of the manual sharp FUE technique include the manual dull punch technique, the use of powered devices with oscillatory or rotating punches, or employing a vacuum apparatus to facilitate atraumatic extraction. Regardless of the technique used, a 5% transection rate is generally acceptable.

Recipient Site Creation and Implantation

  • No matter the harvest technique used (FUE or FUT), the implantation process must also take place in an atraumatic and meticulous fashion. For instance, grafts should only be manipulated using the perifollicular tissue. Furthermore, grafting should be done expeditiously, since prolonged exposure of the FU will cause graft desiccation.
  • Attention to the recipient’s hair pattern is important to promote a natural-looking result. For example, hair along the frontal scalp hairline points anteriorly at an angle of 15 to 20 degrees, while hair follicles in the temporal region are oriented inferiorly. Also, the surgeon should strive to recreate a sharp temporal recess in males and a rounded temporal recess in females. Lastly, the angles and spiraled orientation of the crown should be followed to create a natural result.
  • The recipient sites for the FUs are then created in a random and irregular pattern under magnification using either flat-edged blades or a combination of needles (19 or 21 gauge), with care not to transect the native follicles.
  • The graft is gently placed into the recipient site, with light pressure applied for several seconds with a wet cotton-tip applicator to promote hemostasis and to avoid graft extrusion or “popping.”
  • An emollient or antibiotic ointment and a non-adhesive bandage are placed gently across the donor and recipient sites.

Miscellaneous

  • ROBOT Follicular Unit Extraction: More recently, robotic devices have been developed with potential advantages including more accurate and faster graft harvesting, decreased FU transection rate, and increased implantation accuracy at the recipient site, though comparative studies are lacking. Regardless, the robot offers a promising technique to maximize HT outcomes.
  • Facial Hair Restoration: While the focus of this article was to discuss the nuances of HT for the scalp, facial HT techniques may also be applied to obtain dramatic results when restoring facial hair such as eyebrows, beards, and sideburn