Modern hair restoration surgery is based on a technique known as follicular unit transplantation, in which follicular units are the exclusive structures used as hair grafts. In Part 1 of this 2-part review, we describe how the techniques employed in hair transplantation have evolved into their present forms. Anatomic concepts of specific relevance for dermatologists are discussed, including the distribution and ex vivo morphology of scalp follicular units. Male androgenetic alopecia and female pattern hair loss are the most common reasons for hair loss consultations with dermatologists and will be the primary focus of this review. However, because not all hair disorders are suitable for transplantation, this review will also describe which scalp conditions are amenable to surgery and which are not. Guidelines are provided to help dermatologists better define good and bad candidates for hair transplantation. Other conditions for which hair transplantation surgery is indicated are reviewed.

The second part of this hair transplantation review concentrates on the technical aspects of the surgery. First, we review the 2 main local anesthetics used in hair transplantation, lidocaine and bupivacaine, how to achieve long-lasting local anesthesia, and what techniques can be used to minimize the pain associated with anesthetic infiltrations. Second, we review the 2 donor harvesting techniques currently used: strip harvesting follicular unit transplantation and follicular unit excision. The technical aspects of each technique are described in detail, along with their advantages and disadvantages. Third, the different methods of graft implantation currently used by the majority of hair surgeons are discussed, including premade sites and stick-and-place and the use of tools such as implanters. Fourth, postoperative care, expected results, and the main complications involved in hair transplant surgery are reviewed.

Background: Current no-shave long hair-follicular unit excision (LH-FUE) techniques employ recesses (slots, notches, or grooves) in punch tips to reduce the long-hair shaft break rate (SBR) and graft transection rate (GTR). However, these methods demand advanced skills and extended procedure time. Objective: We aimed to evaluate a skin-responsive FUE technique without the use of recess-tipped punches, accommodating diverse hair and skin types in LH-FUE procedures. Methods and Materials: We retrospectively analyzed patients who underwent this technique using a UGraft Zeus device at five multinational clinics (Mexico, Colombia, India, United States, and Türkiye) from August 9, 2021, to April 11, 2023. Donor zones were pre-operatively graded for expected difficulty using the Sanusi FUE Scoring (SFS) Scale, ranging from class I (low difficulty) to V (high difficulty). Results: Among 152 patients (mean age, 46 years; 146 straight-wavy, 6 curly-coiled hair), most (n=107) were class I donors. The GTR ranged 2.2%-4.3%, and was highest in class IV donors and those with thick-firm scalps. The SBR was 12.2%, and the average graft excision rate (GER; speed) was 440 grafts/h. Only 19G and 18G punches were used. All patients were satisfied with the procedure, with 57.4% reporting that they were "very happy". Surgeon willingness to perform no-shave LH-FUE significantly increased from 1.25 to 4.20 (on a scale of 1-5) after adopting this device. SFS class, skin thickness, and firmness, more than hair curliness, influenced the GTR, SBR, torque, and punch movement duration. Conclusion: Our findings reveal consistent success in conducting no-shave LH-FUE using this skin-responsive device across diverse patients. Notably, success was achieved without recess-tipped punches, resulting in low GTR and SBR, along with a high GER and increased patient satisfaction. These outcomes suggest enhanced procedure speed and ease of use, contributing to a greater willingness among surgeons to adopt this technique.

Hair restoration has become increasingly popular in recent years with both men and women. New technologies such as follicular unit extraction and grafting have made it possible for patients to get a natural looking result with minimal downtime. Men usually experience hairline recession as a result of androgenic alopecia, while women most commonly experience thinning of the crown and vertex, with the preservation of the hairline. However, there is a growing population of women who wish to advance their hairline forward because of congenital high hairline, traction alopecia, or previous facial cosmetic surgery. There are several key differences between the female and male hairline. Understanding such differences and following certain guidelines will help the facial plastic surgeon to obtain beautiful and natural appearing results.

Background: Androgenetic alopecia (AGA) is a pathology involving the aesthetic prognosis. Hair transplantation is among best treatments. The principle of hair micro-grafts during AGA consists in taking hair from the non-androgen-dependent occipital area to transplant them with their root in the sparse androgen-dependent areas. Herein, we report 10 cases of the different types of post-transplant inflammatory complications.

Materials And Methods: We included patients referred to our center by their dermatologists or hair transplant surgeons for inflammatory cicatricial alopecia or hair loss observed after the hair transplant.

Results: Ten patients (eight men and two women) were included. These patients represented 0.08% of all consultations in our center. The indication for hair transplantation was AGA in all of our patients. The technique used for the transplant was follicular unit extraction (FUE) in seven cases and follicular unit transplantation (FUT) strip in three cases. None of the patients had pathology of the scalp or an inflammatory dermatosis before the operation. The inflammatory complications found were lichen planopilaris (LPP) in seven cases, erosive pustulosis of the scalp (EPS) in two cases, and superficial folliculitis (SF) in 1 case.

Conclusion: Our series highlight the rarity of inflammatory complications that occur after a hair transplant. We demonstrate through this work that a hair transplant can trigger inflammatory pathology a few months after the act. We show also, the importance of detecting the rough forms of lichen before an intervention, hence the interest of the systematic dermatoscopic examination during the preoperative consultation.

The design and development of a prototype for a singular robotic hair transplant system capable of harvesting and implanting hair grafts were executed in this study. To establish a proof-of-concept for hair transplant procedures involving harvesting and implantation, a test system using a spherical phantom of the scalp was selected. The developed prototype of the robotic hair transplant system demonstrates the potential to reduce the duration that grafts remain without a blood supply, thereby minimizing hair graft damage. Additionally, the overall operation time for follicular unit extraction is comparatively shorter than that of conventional systems. Results from the robot vision tests indicate an 89.6% accuracy for hair graft detection with a 4 mm hair length phantom and 97.4% for a 2 mm hair length phantom. In the robot position control test, the root mean square error was found to be 1.268°, with a standard error of the mean of 0.203°. These outcomes suggest that the proposed system performs effectively under the conditions of a spherical phantom with a 2 mm hair length and a 5 mm distance between harvests.

CQ5 Is Hair Transplantation Useful?
Comments: Hair transplantation should be performed by experienced surgeons for the benefit of patients who have shown insufficient improvement after treatment with oral finasteride or topical minoxidil.
Description: Although there are no systematic reviews or randomized controlled trials on the benefits of autologous hair transplantation, there are annually 225 800 cases (86.2% in males and 13.2% in females) of transplantation of hair tissue from the occipital area to the affected areas.1 Beehner has reviewed multiple previous reports which indicated that autologous hair transplantation has a graft survival rate of 82.5% or higher,2 a fact that corroborates its use as a standard form of treatment for alopecia.
Although the level of evidence regarding autologous hair transplantation is not remarkably high, the committee assigns this treatment a grade B recommendation only in the cases where it can be performed by a surgeon with sufficient experience and skill. Additionally, the treatment should be a last resort, in cases where oral finasteride treatment or topical application of minoxidil has had an insufficient effect. This decision was made after due assessment of the domestic and international precedents for this treatment and on the degree of the psychological distress caused to the patient by the condition.

This article will provide a brief review of the current concepts in hair transplantation. Currently, hair transplantation creates natural appearing transplanted hair for men and women. Patient consultation is an essential component of a successful procedure. During the consultation realistic expectations are essential and are based on the patient's donor density, caliber of hair follicle, and rate of hair loss. Alternative and adjunctive therapies such as finasteride and minoxidil should be a basic component of any consultation. The only limit to the procedure is the amount of donor hair each patient has available. For the vast majority of patients, elliptical donor harvesting provides the most efficient technique for harvesting hair. Follicular unit extraction can be a useful technique for a minority of patients.