Donor harvesting: Follicular unit excision

Abstract

FUE or follicular unit excision is one of the methods for hair follicle harvesting in hair transplantation. FUE involves harvesting hairs from the donor area, under local anesthesia which is most commonly the scalp but occasionally beard, chest and other parts of the body, using a circular punch less than a mm, mounted on a manual handle or a motorized hand device or more recently a robotic device. First hair transplant was done by Dr Shoji Okuda in 1937. The term “follicular unit extraction” was coined by William Rassman in 2002. The modern era of FUE begins with the work of several surgeons Woods, Rassman, Cole, Harris and Rose. FUE has gone through various stages of development from manual to motorized and blunt to sharp, serrated trumpet and flared punches. Now the use of the robot in FUE with extraction and incision making is also in use. In 2017 nomenclature committee headed by Parsa Mohebi of ISHRS, recommended the term “FOLLICULAR UNIT EXCISION” is most appropriate as it explains the two steps of the process: incision and extraction and incision is done by a physician. FUE is a surgeon based time-consuming procedure with the long learning curve. Use of motorized device and sharp punches has certainly helped to increase speed in an experienced hand. FUE method of hair transplant is the most demanding procedure. If done properly it is a safe procedure. with the experience, use of better quality of instrument the disadvantages of FUE like transection can be reduced. The above informations were collected from various papers published in authentic journals and textbooks.

A Novel Follicular Unit Excision Device for All-Purpose Hair Graft Harvesting

“…Generally, large punches register fewer graft transections. 5 The flaring of the punch ( Figure 1 ) mitigates transection rates compared with straight punches of the same diameter. However, the diameter of the funnel-shaped rim (responsible for the first skin cut and wound size) of an ordinarily flared punch increases the diameter of the punch to exceed the diameter of the long cylinder ( Figure 3A ).…”

“…Overall, the all-purpose FUE device incorporates torque such that, at the appropriate torque and speed settings, the punch stops after separating the graft from its lateral attachments ( Supplementary Video 3 ). Thus, instead of relying on the practitioner’s experience of knowing when to pull out the punch or using mechanical guards 5 , 9 or an automatic timeout mechanism of depth control, 24 the all-purpose FUE device intuitively takes its cue mainly from the resistance of the tissue to determine the appropriate depth. 17…”

“…In previous FUE devices, the operator must align the punch’s long axis to precisely align with the long axis of the hair exit angles on the skin or risk graft loss. 4 , 5 , 9 In contrast, the novel device corrects for roughly 20–40 degrees of misalignment through its MAN feature. Thus, the practitioner does not need to be exact in punch-hair-axis alignments.…”

“… 4 Additionally, they do not adequately perform when faced with changing skin and hair characteristics between and within patients from one body/head area to another. 5 , 6 Consequently, not everyone can benefit from the advantages of FUE over other hair transplant methods. Some devices perform excellently in one type of harvest but not in others.…”

History of follicular unit excision

“…He suggested use of the term "Follicular isolation technique" instead of FUE. 5 He said that, the extracted grafts did not always contain all the follicles of a single follicular unit.…”