Robotic Follicular Unit Extraction in Hair Transplantation
Robotic Follicular Unit Extraction in Hair Transplantation
Marc R. Avram, MD,* and Shannon A. Watkins, MD†
BACKGROUND In recent years, there has been a shift toward minimally invasive procedures. In hair trans- plantation surgery, this trend has manifested with the emergence of follicular unit extraction (FUE). Recently, a robot has been introduced for FUE procedures.
OBJECTIVE- To determine the transection rate of a robotic FUE device. In the attached article, the authors discuss the procedure, technical requirements, optimal candidates, advantages, and disadvantages of robotic FUE compared with the standard ellipse.
RESULTS- Optimal candidates for robotic FUE are those with dark hair color who can sit for 45 to 120 minutes and are willing to shave a large area for donor harvesting. The main advantages of robotic FUE compared with the standard ellipse are its minimally invasive nature and the lack of a linear scar.
CONCLUSION- The robot is a new and innovative method for FUE hair transplantation of which hair transplant surgeons should be aware.
In the 1990s, hair transplant surgery underwent a revolution in the graft size used for transplantation. From the 1960s into the mid 1990s, 2 to 4 mm grafts containing 10 to 20 hair follicles were the standard graft used in the procedure. In spite of its scientific success, they were often a cosmetic failure because they resulted in a “pluggy” unnatural appearance. In the 1990s, there was a shift toward smaller graft sizes. Currently, the follicular unit, which contains 1 to 4 hair follicles, is the standard graft size used in transplant surgery.1,2 This shift in graft size has allowed patients to consistently grow naturally appearing transplanted hair, as it mimics the natural size of follicular groupings on the scalp1 (Figure 1). In addition, the use of follicular groupings eliminates textural changes and scarring in the recipient area. Large grafts containing 10 to 20 hair follicles required larger recipient sites, which resulted in unnatural “cobblestone” scarring on the scalp. Recipient sites for follicular groupings are less than
In the era of follicular unit transplantation, the only visible scar on the scalp is the linear scar left from the donor ellipse. For the majority of men and women, a linear scar has no short or long- term practical effect. Their existing donor hair will camouflage the scar. A linear scar can create an issue, however, for some patients who wear their hair shorter or want the option of a shorter hairstyle in the future. In addition, there has been an inexorable trend in all surgical procedures toward minimally invasive procedures, which result in less scarring and quicker recovery times.
Donor Harvesting Techniques
Over the past several years, the focus of discussion in the field has begun to shift away from the size of the graft used to transplant hair toward the harvesting method used to obtain the donor grafts. For decades, 2 to 4 mm punch trephines were used to obtain donor hair from the posterior scalp. Typically, the grafts were removed and wounds were allowed to heal by secondary intention. This resulted in widespread “hon- eycomb” scarring (Figure 2). In 1994, the concept of elliptical donor harvesting, also known as strip har- vesting, was introduced and has been the standard method for obtaining donor grafts.3 It is based on the same dermatologic surgery techniques used in removing nevi, skin carcinomas, and cysts. It allows efficient harvesting of hundreds to thousands of fol- licular groupings. As with any cutaneous excision, there is a scar created from removing the donor ellipse. For the majority of patients, this is neither a medical nor a cosmetic issue. For a minority of patients, medical and cosmetic challenges may arise. A small percentage of patients will develop hyper- trophic or broad scars. Others feel limited in the hair styling options because of the donor scar. For these
Follicular Unit Extraction Versus Elliptical Donor Harvesting
The concept of follicular unit extraction (FUE) was introduced in the early 21st century and refined over the past decade.4–6 Follicular unit extraction used the same concept of using a steel trephine to harvest donor hair, but instead of being 2 to 4 mm in diameter as was used in the past, the FUE punches range from 0.8 mm to 1.2 mm. This technique is a natural extension of the concept of follicular unit hair transplantation—the utilization of individual follicular groupings in the recipient and donor sites.
Challenges of this technique include the following: increased risk of transection of hair follicles, operator fatigue when harvesting hundreds of follicular groupings, and appropriate spacing of harvested grafts to yield the maximum amount of donor hair without creating the appearance of a depleted donor density.6 Throughout the posterior scalp, the angle of hair growth varies, which presents a challenge to surgeons. Magnification and excellent lighting reduce but do not eliminate the risk of transecting follicles. Compounding this challenge is the need to remove dozens to many hundreds of follicular groupings for each case. Harvesting larger numbers of grafts can result in increased operator fatigue and a higher rate of transected hair follicles. Some experienced sur- geons are able to harvest large numbers of follicular groupings with minimal transections, but others are unable to do so.
To improve the accuracy and efficiency of FUE, numerous FUE devices have been developed; of which some are motorized, some are suction assisted, and some are single user-directed robotic system. The NeoGraftautomatedhairtransplantsystem,7–9 SAFE (surgically advanced follicular extraction) system,10 and ARTAS Robotic System (Restoration Robotics, Inc, San Jose, CA) are a few of the more well-known FUE devices on the market. In this article, the authors discuss about robotic follicular unit extraction with the robot.
Robotic Follicular Unit Extraction
The robotic system was approved by the Food and Drug Administration for hair transplantation in 2011. This robotic device is used to harvest follicular units from the donor region (Figure 3). A 1-mm punch is attached to the robotic arm consisting of a “needle- within-needle”; there is a sharp inner punch sur- rounded by a blunt outer punch. The sharp inner punch creates a shallow 1-mm incision, subsequently, the blunt outer punch spinning at 400 to 800 rpm dissects deeper and separates the follicular units from surrounding tissue. A suction system attached near the punch elevates the follicular unit from the surrounding skin allowing for easier extraction of the graft. A combination of stereoscopic cameras managed by image processing software allows the sharp and blunt punches to identify the precise angle and direction of hair growth. This continuous imaging feedback allows the robot to precisely harvest each follicular grouping. Because of the high level of automation, the robot is able to remove 400 to 600 grafts per hour.11–13 The software requires a minimum distance of 1.6 mm between extracted follicular groupings to minimize risk of overharvesting donor hair. In Table 1, the authors compare strip harvesting with robotic FUE donor harvesting.
See the attached article for more information.