Hair Transplantation 

Updated: Dec 13, 2017
Author: Jeffrey S Epstein, MD, FACS; Chief Editor: Arlen D Meyers, MD, MBA 

Overview

Background

Hair loss occurs in more than 60% of men and in approximately 10% of women. Although a lack of scalp hair can potentially increase the risk of actinic damage and skin cancer, male and female pattern baldness are conditions that are, with few exceptions, treated electively.

Balding is a major concern for many, and surgery to treat hair loss (ie, hair transplantation) is the most common cosmetic surgery procedure performed on men today. Yet, the market for hair transplantation is dwarfed by the immense market for products that treat hair loss without surgery. These products, which include shampoos, hair-care cosmetics, scalp massagers, laser combs, and many more, have no proven efficacy except for their ability to temporarily increase the volume of existing hair, resulting in a denser appearance than before. Exceptions are the two medications the US Food and Drug Administration (FDA) approved: minoxidil (Rogaine, available over the counter in the United States) and finasteride (Propecia, available by prescription only for men), which have limited but definite benefit.

Interest in hair transplantation will probably increase as knowledge that most modern hair-transplantation techniques can create virtually undetectable restoration spreads, as shown below. To this day, hair transplantation remains the treatment of choice for most patients with hair loss.

Case 1. Views before and 6 months after a procedur Case 1. Views before and 6 months after a procedure performed by using 2000 follicular-unit micrografts.

One of the most rapidly growing segments of hair transplantation is hair transplantation in women. Surgical hair restoration was developed for and has traditionally been used in males. Newer techniques are more adaptable to females.

Hair transplantation is used to treat various forms and degrees of permanent alopecia in both men and women. Intact hair follicles may be harvested from within the safe donor area (SDA) of a patient's scalp by either follicular unit strip surgery (FUSS) or follicular unit extraction (FUE); each harvesting method has unique advantages and disadvantages. The refinement of follicular unit transplanting over the last decade has led to markedly improved hair survival and natural-appearing results (see the image below).[1, 2, 3, 4, 5]

Case 2. Views before and after 3500 follicular-uni Case 2. Views before and after 3500 follicular-unit micrografts performed in 2 procedures.

Problem

Some say, "A bad hair day is better than a no hair day." For millions of individuals, hair loss is a major problem associated with loss of self-esteem, insecurity, and even depression. Hair loss can range from early thinning or hairline recession to complete loss of hair along the top and upper sides of the head.

A full head of hair contains approximately 100,000 hairs. (People with red or blonde hair have somewhat more than this.) The loss of up to 30% of the number that was present during the peak of adolescence that occurs by middle age is part of the normal aging process. For thinning to become cosmetically noticeable, at least 50% of the hairs must have fallen out in a particular area. Loss of a smaller percentage than this generally does not result in the cosmetic appearance of hair loss. In addition to the loss of the number of hairs, the hair loss process causes individual hairs to thin, which further contributes to the appearance of hair loss.

The Norwood Classification System recognizes and categorizes the typical sequence of the hair loss process in men.[6] Early in the process (types 1-3), the hairline recedes, typically led by frontotemporal recessions. In the latter stages (types 4-7), progression of hair loss at the vertex (crown) gradually meets and joins the progressive hairline recession, resulting in varying sizes (in both coronal and sagittal dimensions) of the confluent vertex with frontotemporal regions of baldness.

For women, the development of androgenic alopecia is classified into three stages. The typical pattern of hair loss in women is progressive diffuse thinning in an oval area along the top of the scalp. Hair loss along the hairline is usually spared.

During the 1990s, leaders in hair transplantation debated several topics. Out of the debates emerged several commonly (though not unanimously) accepted truths.

First is the superiority of hair grafting versus bald-scalp reduction and scalp-flap surgery in almost all situations. Second is the inferiority of lasers to conventional cutting devices to form the recipient site. Third is the acceptance of large-session micrografting, also termed the megasession, in which 2000 or more grafts can be transplanted safely in a single procedure.

Nearly all hair-transplant specialists agree on the superiority of follicular-unit micrografting over traditional micrografting and minigrafting. Although follicular-unit micrografting is technically more demanding and time-consuming than other procedures, it yields superior results in terms of creating a natural appearance because hairs are transplanted as they grow naturally in the scalp. The procedure also enables dense graft placement when desired because individual grafts are small and thereby permitted small recipient sites and closer spacing. In addition, follicular-unit grafting reduces accidental transection of hair follicles during the graft-dissection process because dissection is performed under microscope visualization; therefore, wastage of valuable donor hairs can be reduced.

The future of hair restoration is exciting, primarily because of medical advances. Improved effectiveness of control of hair loss coupled with minimization of adverse effects result from the use of 5-alpha reductase inhibitors that are specific for the hair follicle or from the use of medications that work by alternate pathways. In addition, gene therapy may have future application in hair loss treatment. The genes that cause alopecia can be located and potentially replaced with genetic sequences not associated with hair loss.

Hair cloning (technically cell multiplication) may offer the surgeon a virtually unlimited supply of donor hairs. By cloning multiple copies of just a few donor hairs, patients with even extensive hair loss can expect complete scalp coverage, all with minimal donor-site morbidity. Most likely, follicle stem cells will be multiplied then injected into areas of thinning to initiate the regrowth of hairs. Candidates for hair cloning include those with advanced hair loss and those with scarring or poor supplies of potential donor hairs because of burn injury or previous poorly performed hair transplantations.

Mechanization of the hair-transplantation process is perhaps the only way to improve the process of follicular-unit transplantation. Instruments capable of rapidly and accurately dissecting the grafts and atraumatically placing the grafts will speed the process and reduce reliance upon assistants. However, hair transplantation will remain an aesthetic procedure that requires a skilled surgeon to create natural-appearing results.

According to the International Society of Hair Restoration Surgery, hair loss affects 21 million women in the United States, with varying impact on their psychological, social, and emotional well-being. Hair loss in men can be socially acceptable, and, in fact, deemed attractive or alluring. Conversely, society generally has less acceptance of thinning of hair or baldness in women. Women with hair loss often find it more difficult to share their feelings about hair loss with loved ones or friends or even their physicians.

Anatomy

The scalp is divided into five layers, which are easily remembered by the mnemonic SCALP, which represents, in order from outermost to innermost layer, the skin, connective subcutaneous tissue, galea aponeurosis, loose connective tissue, and periosteum over the cranium.

The skin contains all the epidermal appendages, including hair follicles, which extend into the connective subcutaneous layer. In areas that have undergone hair loss, thinning of the outer two layers usually occurs. This situation can be appreciated when one compares the thickness of the scalp in recipient areas with that in donor areas.

The subcutaneous layer is well vascularized and contains the main penetrating branches of the named main arteries that travel primarily along the external surface of the galea. The importance of staying superficial along the connective subcutaneous tissue layer (when one makes slit recipient sites to avoid compromising circulation) has only recently become apparent. The scalp has an excellent blood supply. The supraorbital, supratrochlear, superficial temporal, postauricular, and occipital arteries are the primary vessels, and they typically travel with the veins.

The galea aponeurotica is a nonelastic layer that connects the frontalis muscles anteriorly with the occipitalis muscle at its posterior aspect. The temporoparietal fascia, in which the superficial temporal artery travels, is also connected to the galea. The galea sliding over the loose connective-tissue layer allows for most scalp mobility. This loose connective-tissue layer and the periosteum below have minimal sensory innervation.

The sensory innervation of the scalp closely follows the vascular supply. At the anterior aspect, the supraorbital and supratrochlear nerves provide sensation to the anterior half of the scalp. On occasion, sensation to the frontal scalp can diminish for several weeks when a large number of graft recipient sites are made along the hairline. The occipital nerve serves the posterior half of the scalp, whereas the supraauricular and superficial temporal nerves contribute innervation from the sides.

Perhaps no anatomic feature of the scalp is more important with regard to hair transplantation than the microscopic distribution of hair. Scalp hairs usually do not grow individually; they most often grow in tiny follicular-unit bundles, which usually contain 2-3 hairs and occasionally 1 or 4 hairs. A follicular unit contains these 1-4 terminal hairs, a sebaceous gland element, and insertions of the arrector pili muscles, all wrapped in an adventitial tissue sheath. These follicular units are dispersed throughout the scalp, where non–hair-bearing skin constitutes up to 50% of the total tissue. By transplanting only these follicular units and dissecting away the 50% of unnecessary non–hair-bearing tissue, the most natural-appearing results can be attained.

See Scalp Anatomy and Hair Anatomy for more information.

Pathophysiology

In men, pattern baldness has been established as an androgen-mediated miniaturization process of genetically susceptible hair follicles. Women with pattern baldness are presumed to undergo the same process.

Pattern baldness requires linking of the hormone dihydrotestosterone (DHT) to susceptible hair follicles. In the body, DHT is created when the enzyme 5-alpha reductase converts testosterone. This conversion takes place in the bloodstream and locally in the scalp and other body tissues. DHT acts on genetically susceptible hair follicles to cause miniaturization of the hair, which eventually leads to follicle death.

Donor versus recipient dominance refers to the ability of hair grafts taken from an occipital donor area to grow and survive after transplantation to the frontal recipient site of alopecia. This phenomenon is explained by the presence of 5-alpha reductase in the cells of the recipient hair follicles. Again, this enzyme, found in skin, is responsible for conversion of testosterone to DHT. Even normal circulating amounts of testosterone may be excessively converted to DHT or the hair follicle may be abnormally receptive to DHT, creating androgenic alopecia. The donor follicles from occipital regions have less or no enzyme and thus are not influenced by hormonal factors. The mesenchyme-derived dermal papilla at the base of the mainly epithelial hair follicle controls the type of hair produced. This is probably the site through which androgens act on follicle cells by altering the regulatory paracrine factors produced by dermal papilla cells.

Recipient dominant conditions refer to a diseased recipient area, which destroys the healthy donor follicle when transplanted. These conditions include cicatricial or scarring alopecia, such as discoid lupus erythematosus, lichen planopilaris (lichen planus of skin and hair follicles), and other active scarring skin diseases of hair and scalp that attack the healing donor follicles.[7] These diseases can be treated medically and when the condition resolves, healthy hair grafts can be placed into the resultant but quiescent scar.

Etiology

Hair loss in men almost always is due to androgenic pattern baldness, which is usually referred to as male pattern baldness. Although the exact cause of pattern balding is unclear, the trait is transmitted by means of a polygenic type of inheritance. Anecdotal reports indicate a stronger link to men on the maternal side of the family than on the paternal side. Male pattern baldness is a progressive process that continues for the rest of an individual's lifetime. The eventual degree of hair loss is typically more advanced with a younger age of onset.

In women, most hair loss is also genetic, although women have an increased incidence of hair loss caused by medical conditions, such as hormonal imbalance, trichotillomania, and poststress telogen effluvium. Interestingly, even with androgenetic alopecia in women, there appears to be an additional inflammatory contribution to hair loss, as scalp biopsies often reveal a localization of lymphocytic folliculitis around the stem-cell–containing bulge region of the hair follicle.[8]  As with male pattern baldness, female pattern androgenic hair loss is progressive.

Alopecia areata is an autoimmune hair cycle shift that can be present in any area of the scalp, including donor areas, so that all scalp hairs may be involved, leaving no healthy donor follicles. It also resolves with medication and topical therapy, with hair regrowth in most instances. Diffuse female alopecia also involves the entire scalp and thus is not amenable to hair transplantation.

The most common cause of hair loss in women is androgenetic alopecia. Unlike androgenetic alopecia in men, women tend to have diffuse thinning, often sparing the frontal and occipital regions. Differentiating androgenetic alopecia in women from other causes of alopecia is important. A positive family history usually accompanies androgenetic alopecia. Increased sensitivity to androgen with normal serum hormone levels is present. The pattern usually preserves the frontal hairline. Miniaturized hairs with varying lengths and diameters are present.

Androgenetic alopecia must be differentiated from androgen excess disorders, which are often the result of adrenal, ovarian, or pituitary tumors or disorders.[9] Be suspicious of androgen excess if the following are present: hirsutism, menstrual disorders, cystic acne, galactorrhea, virilization with temporal recession, lowering of voice, increase in muscle mass (especially the shoulder girdle), and infertility. The workup is best performed by an endocrinologist or gynecological endocrinologist.

Rapidly thinning hair may suggest telogenic effluvium or endocrinopathies. Telogenic effluvium is best treated with minoxidil. Telogenic effluvium may be an acute generalized hair loss over the scalp, such as that occurring with stress, anesthesia, or childbirth. Hair regrowth usually occurs 4-12 months later. Chronic telogenic effluvium occurs more slowly and may be confused with androgenetic alopecia. Unlike the latter, chronic telogenic effluvium is not usually revealed in family history.

Hair loss in women can be caused by numerous sources, such as hypothyroidism, various medications, systemic disorders, trauma (eg, surgical trauma, burn alopecia), and infections. Telogenic effluvium and androgenetic alopecia can coexist, with an episode of telogenic effluvium unmasking coexistent androgenetic alopecia.

Scarring alopecia of unknown etiology is best evaluated by biopsy and dermatologic workup.

The other large group of women presenting for hair transplantation are those with postsurgical scarring. Usually these patients have undergone browlifts and facelifts.

Interest in eyebrow and eyelash transplantation has recently increased. The use of micrografting techniques with microscopes used for graft cutting has greatly improved these techniques. More recently, the use of follicular unit extraction (FUE), which is graft harvest with tiny micropunches, can decrease donor scarring.[10, 11, 12, 13] Eyebrow alopecia may result from plucking, trauma, or inherited thinning. Eyelash alopecia may also be traumatic, inherited, or caused by compulsive pulling or plucking.

Epidemiology

The incidence of hair loss in men approaches 60% by the age of 60 years. In women, this incidence is considerably lower, that is, approximately 10% at a similar age.

Alopecia is a common problem within our population. In the United States, it is estimated that 35,000,000 men and 21,000,000 women experience hair loss. It is so common in men that it is actually accepted as normal.

Androgenic alopecia in females is an increasingly frequent problem based on heredity and hormonal change. There is much speculation concerning the more frequent occurrence of this problem among premenopausal women, but the answer remains obscure. Both of these conditions are considered "donor dominant" and thus amenable to hair transplant surgery.

Among racial groups, whites have the highest incidence of hair loss, African Americans have lowest incidence, and Asians have an incidence between the two.

 

Prognosis

Patients must be given realistic expectations. Furthermore, the importance of joint planning by the patient and the surgeon for future hair loss cannot be underestimated.

The transplanted hair follicles typically appear to grow in the immediate postoperative period. Within a month, the graft follicles enter the telogen phase and are all shed. Hair regrowth then takes approximately 4 months, but the hair continues to improve in quality and quantity over the subsequent 2-4 months. Growth stabilizes at about 1 year and reports have indicated graft survival rates of over 95% in experienced hands. Even 18 months after surgery, newly transplanted hairs have been observed to appear for the first time.

The present techniques and technology of hair transplantation surgery can give a proper candidate realistic and natural appearing transplanted hair. Using 2 or 3 hair transplant sessions, the candidate has a successful outcome.

Case 2. Views before and after 3500 follicular-uni Case 2. Views before and after 3500 follicular-unit micrografts performed in 2 procedures.
Case 2. Close-up view of the hairline of a patient Case 2. Close-up view of the hairline of a patient after transplantation of 3500 follicular-unit micrografts performed in 2 procedures.

Patient Education

As with any surgical procedure, thorough counseling before hair-restoration surgery is critical. Patients require education to make informed decisions regarding this elective procedure, ie, whether to undergo it, and, if so, which procedures. Because hair restoration is cosmetic surgery, discussing patients' areas of concern, explaining treatment options, and providing a realistic picture of expected results are important.

Patients should be provided with written information regarding both preoperative and postoperative instructions. After reviewing the patient’s list of medications to rule out any that may adversely interact with anesthesia administered during the procedure, it is important that various medications that may affect bleeding time be discontinued. Patients should stop taking all aspirin-containing medications, vitamin E, and ginkgo 10 days before the procedure and all nonsteroidal anti-inflammatory drugs (eg, ibuprofen) and alcohol 3 days before. To further reduce the risk of bruising and edema, patients are instructed to take vitamin C 2000 mg daily for 1 week before surgery. If the patient is to receive intravenous or twilight sedation, they should receive nothing by mouth (NPO) 8 hours before the procedure.

Appropriately aligning patient and physician expectations is critical during the initial evaluation and consultation. Understanding the limits of a patient’s donor hair reserves, their hair characteristics, and their goals and motivation for undergoing hair transplantation can best help evaluate and articulate a projected outcome. Establishing this mutual understanding is one of the most effective ways to increase overall patient satisfaction.

 

Presentation

History

Male pattern baldness follows a classic pattern that is best illustrated by using the Norwood Classification System, which ranges from type 1 (minimal frontotemporal recession) to type 7 (loss of all but a small rim of hair).[6] Types 2-6 categorize the typical progression of hair loss.

The clinical presentation in women differs somewhat from that of men. In women, hair loss along the hairline is typically spared, with thinning throughout the top and upper sides of the head is more diffuse in women than in men.

In one suggested scenario, preoperative screening consists of a health-history questionnaire that includes questions about easy bruising, anesthesia problems, allergies, mitral valve prolapse or other conditions necessitating preoperative antibiotics, and all current medications (including herbal remedies). Study results have confirmed the superiority of good history taking and physical examination compared with any blood screening test for determining a patient's medical suitability for surgery.

Physical Examination

Upon initial patient evaluation, the physician must first determine the etiology of the patient’s hair loss. Only after first ruling out (1) systemic causes such as thyroid abnormalities, polycystic ovarian syndrome, or iron-deficiency anemia; (2) dermatologic causes that may be treated medically; (3) and telogen effluvium (temporary hair loss that resolves over a few months’ time), should a surgical approach to hair loss be considered.

Complications

When performed properly, the results of hair transplantation are virtually undetectable. However, complications can arise from errors of technique, poor planning, and unpredictable patient factors.

As with any surgery, hair transplantation poses possible risks. Excessive bleeding due to undiagnosed coagulation disorders or secondary to medications can be bothersome at the least and (in rare cases) life threatening at the worst. Infections and anesthesia problems are two other potential, although unlikely, complications.

Complications more unique to the hair transplantation procedure are rare but can occur. Scarring of the donor site can include hypertrophic scar formation due to excessive tension and perhaps even a tendency toward keloid formation. Alopecic scar formation can result from excessively tight suture placement or from hair follicle cauterization. Scarring of the recipient site was more common when large-graft transplantation was performed. Such scarring included ridging, cobblestoning, and skin hypopigmentation.

Poor hair growth can occur and probably is largely dependent on technique. Graft desiccation, rough handling of the grafts, and faulty graft preparation can result in limited hair growth. Lack of growth must be distinguished from delayed hair growth because transplanted hairs occasionally require as long as 12 months to grow. Telogen effluvium or loss of original hairs in transplanted areas, usually an avoidable condition, can result from poor circulation or inadvertent trauma to already existing hair follicles, thus producing an initial early thinning of hair that can range from mild to cosmetically disturbing. Hairs usually return in 1-2 months, but this can be a difficult situation.

Errors of technique and of poor planning are preventable but occur all too often. The most common of these technical errors, which results in a transplanted appearance, is the use of excessively large grafts and unaesthetic hairline design. The importance of using 1- and 2-hair grafts, placed in the proper direction to create an irregular hairline of gradually increasing density as the surgeon proceeds centrally, cannot be overstated.

Failure to anticipate future hair loss in planning hairline restoration can result in an unnatural appearance as the patient ages. One of the most common problems can be development of large bald areas between the lateral aspects of the parietal hairline and the temporal peaks caused by recession of the temporal areas. Transplanting of the crown in a young individual who eventually develops excessive baldness can result in a circular region of transplanted hair surrounded by a rim of bald scalp.

Undesirable hair transplantation results can usually be dramatically improved by using a number of reparative techniques. However, the goal of hair-transplant surgeons should be the prevention of undesirable results.

Complication rates in hair restoration surgery are very low. In one study, they occurred in 4.7% of patients and included enlarged scar (1.2%), folliculitis (1%), areas of necrosis in the donor area (0.8%), keloids (0.4%), bleeding (0.2%), hiccups (0.2%), infection (0.2%), and pyogenic granuloma (0.2%).[14, 15] This survey included physicians whose practice was not limited to hair transplantation, where the percentages are higher than those reported elsewhere.[16]

 

Workup

Approach Considerations

When healing or bleeding characteristics are concerns, consider performing screening blood tests, including tests of following:

  • CBC count with platelets
  • Prothrombin time (PT)
  • Activated partial thromboplastin time (aPTT)

Further testing (eg, chemical profile) is occasionally performed as the patient's medical condition dictates.

In female patients, extensive workup is indicated to rule out potentially treatable causes of the hair loss. Include tests of the following:

  • CBC count
  • Total iron and ferritin
  • Thyroid function tests and thyroid-stimulating hormone
  • Total and free testosterone
  • Dehydroepiandrosterone (DHEA) sulfate, in cases of irregular menses

Further testing (eg, ECG) is occasionally performed as the patient's medical condition dictates. It also may be prudent to screen for antibodies to HIV hepatitis B and C.

Classification

Staging alopecia into both pattern and degree of severity can be accomplished through the Hamilton classification. Patients with Hamilton patterns I and II have very early limited alopecia requiring minimal treatment if accepted as candidates. Conversely, patients with patterns VI and VII may no longer be candidates for the surgery since their alopecia is so extensive. The very best candidates fall into patterns IV to V, which produce the best, most natural results. See the image below.

 

Treatment

Approach Considerations

Nearly all men and most women who have androgenic or inherited pattern baldness can be treated with hair transplantation. As in all other elective cosmetic surgeries, the most important patient selection criterion in hair transplantation is the individual's motivation. Results of hair transplantation are usually most dramatic when the procedure is performed on individuals with advanced degrees of hair loss. In general, the greater degree of hair loss, the larger number of grafts transplanted.

Hair transplantation may not be the most effective therapy for some medical causes of hair loss; in some instances, it exacerbates the condition. Therefore, workup to rule out other treatable causes of hair loss is important, especially in women, in whom nongenetic etiologies for the hair loss are more common than in men.

In addition to male pattern baldness and female pattern baldness, a variety of conditions can be successfully treated with hair transplantation. Scarring of the scalp due to trauma or surgery and hair loss due to traction (seen with extended wearing of hair pieces or trichotillomania) can be repaired with hair transplantation. Finally, hair transplantation can be successfully used to restore hair to the eyebrows; eyelashes; beard, mustache, or goatee area; and even to areas of the body, such as the pubis or chest.

Individuals must be motivated to undergo hair transplantation. Some surgeons conduct a formal psychological evaluation by means of lengthy questionnaires and examinations. The consultation helps ensure the patient is mature enough to decide to undergo the planned procedure. A prospective patient who has realistic motivations and expectations before the procedure is likely to be happy after the procedure. Honest and thorough preprocedural consultation is an extremely important part of the process.

Poor medical health is a potential contraindication for elective surgery of any kind. Individuals cannot be taking anticoagulants (eg, warfarin, aspirin) before the procedure. Good surgical judgment must be exercised when one considers surgery in individuals with potentially complicating medical conditions. Age is not a medical contraindication, as these procedures have been performed on men in their late 70s. However, ensure that such patients provide medical clearance from their internist.

Perhaps no single hair-loss condition calls for more conservatism in judgment than premature male pattern baldness. Teenagers and men in their early 20s are particularly self-conscious about hair loss because most of their peers still have full heads of hair. These young men often hold unrealistic expectations, desiring a youthful hairline that will not be appropriate as they age. Worse, early surgical correction uses a large number of donor hairs, which will be sparse in the future, potentially resulting in an unnatural look and a disappointed patient.

In general, attempt to delay the procedure in individuals in their 20s or younger. When counseling young men about hair loss, it is advised to use a conservative approach to give patients time to consider hair transplantation. If the patient and surgeon agree on transplantation, restore a relatively high hairline and encourage the patient to use minoxidil or finasteride for the crown region. Perhaps in the future, as effective medical therapies that end or substantially slow male pattern baldness progression become available, a less conservative approach can be taken.

For a number of medical conditions that are associated with or that can cause hair loss, treatment with hair transplantation is not appropriate. Examples are the active phases of alopecia areata, lupus, and infections. Scalp conditions, such as vitiligo and psoriasis, must be evaluated because hair transplantation can aggravate them.

The scarring alopecias are nondominant, and, while active, do not respond to hair transplantation. These include discoid lupus erythematosus, lichen planopilaris, and other cicatricial alopecia.[17]

Both men and women may be deemed candidates for hair restoration surgery as long as their donor area (both current and projected) is able to yield a sufficient number of hair follicles to adequately address the projected recipient area (a calculation termed “donor to recipient area ratio”). A family history of hair loss in both the maternal and paternal branches should be investigated and compared with standardized scales of hair loss in women and men (eg, Norwood Pattern, Ludwig Pattern). Young patients (in their 20s) with a limited hair density in their donor area coupled with a projected Norwood Type VII or greater hair loss, for example, will almost certainly not have an adequate number of permanent “fringe” hair follicle reserve to address the future recipient area and often cannot be considered candidates for the procedure.

Helpful screening technology that enables quantitative microscopic donor area measurements (eg, folliscope) aids physicians in patient candidacy evaluation by helping to discern between terminal and vellus (or miniaturized) hairs.[18] Young patients who possess more than 20% miniaturized hairs within their safe donor area may not ultimately benefit from the procedure because, over time, the transplanted hairs may not persist.

Medical Care

Only two medications, minoxidil and finasteride, have received approval from the US Food and Drug Administration (FDA) for treating hair loss. Active clinical research is continually conducted to search for medications that are more effective than these, with pharmaceutical companies eager to market a product that more than 50 million Americans may desire.[19]

Minoxidil (Rogaine) is a liquid applied directly to areas of the scalp undergoing hair loss. Originally indicated for the treatment of severe hypertension, minoxidil slows the progression of hair loss and causes fine hair regrowth in the back half of the scalp in 25-40% of men. Both the 2% (available in generic form) and 5% concentrations (ie, Extra-Strength Rogaine) are available over the counter. Both medications elicit few reported adverse effects; the most common are heart palpitations and headache. In women, the 2% concentration has a response rate similar to that seen in men, helping 20-40% of women retain their hair and, occasionally, achieve hair regrowth.

Minoxidil should be applied twice daily. Like finasteride, minoxidil must be used continuously to maintain hair regrowth. Otherwise, on cessation of the drug, most of the strengthened hairs fall out. The exact mechanism of action of minoxidil is unknown, but it may work by means of local vascular dilation, prolongation of the anagen (growth) phase of the hair follicle, or nonspecific occupation of dihydrotestosterone (DHT)–binding sites in the hair bulb.

Some physicians recommend the use of minoxidil after transplantation. Application to the grafted areas once per day can shorten the interval between the procedure and the growth of transplanted hair from 4 months to fewer than 3 months.

Finasteride (Propecia) is more effective than minoxidil in treating male-pattern hair loss. This 5-alpha reductase inhibitor blocks conversion of testosterone to DHT, the hormone thought most responsible for the miniaturization and eventual involution of scalp hairs in male pattern baldness. Finasteride 1 mg taken orally once per day is effective in approximately two thirds of men. The major benefits of finasteride are the slowing and occasional cessation of hair loss and even the potential regrowth of hairs, primarily in the back half of the head.

Several benefits accrue from the addition of finasteride in individuals undergoing hair transplantation procedures. First, finasteride potentially reduces the need for further procedures, increasing hair allocation to the anterior and middle scalp, areas that do not respond to medication. Second, by potentially minimizing and even reversing the miniaturization process of hairs in the back half of the scalp (including hairs in the donor strip along the back of the head), finasteride can increase the density of those transplanted hairs, thus improving surgical results. Although uncommon, adverse effects can occur and include a less than 2% published incidence of reduced libido and decreased sexual function.

A new treatment modality to receive FDA approval is low-level laser light therapy. This poorly understood treatment involves the several-time weekly application of a laser-emitting device to "stimulate" hair growth of existing miniaturized hairs. It is not clear whether this technique has the equivalent benefits of medical treatments minoxidil or finasteride, but it does appear to be tremendously valuable, in particular slowing down shedding of hair. While the use of low-level light therapy can increase hair caliber in both men and women, any aesthetic improvement is more appreciable in women than in men.[20]

Surgical Care

Surgical hair restoration is the procedure of choice for restoring hair. The concept behind all forms of hair restoration is redistribution of hair rather than addition of new hair. Three hair-restoration procedures have traditionally been available: hair grafting, bald scalp reductions, and scalp-flap surgery. Today, hair grafting accounts for more than 99% of procedures performed. Hair grafting has a high success rate with a low incidence of complications, it is performed in the outpatient setting with little surgical preparation or specialized setup, and (most important) patient acceptance is high.

Bald scalp reduction is of historic interest only. It involves the excision of alopecic scalp. The excised area typically consists of the crown and occasionally extends anterior to the middle scalp. Relatively popular during the 1980s through the mid 1990s, scalp reduction is performed infrequently today. Reducing substantial areas of bald scalp without causing abnormal hair growth, scarring, and marked patient discomfort is difficult, and most surgeons recommend options other than bald scalp reduction for treating hair loss on the middle and posterior scalp.

Few surgeons perform scalp-flap surgery because of the need for specialized surgical training in the technique. In addition, most patients are not ideal candidates for the procedure unless they are motivated, unless they are in their mid 40s or older, and unless they seek a dense hairline with relatively limited hair loss restricted to the anterior scalp. A single scalp flap can contain as many as 10,000 hairs, resulting in the creation of a dense hairline in just 2-3 procedures performed in an interval of several weeks. Complications of scalp-flap surgery (including flap necrosis) can be devastating, although they are rare when an experienced surgeon performs the procedure.

Hair grafting, the most common hair-restoration procedure, can be performed by using different techniques. From the early 1990s until recently, transplanting with micrografts (1-2 hairs), often combined with minigrafts (3-5 hairs), was considered state of the art. Today, most surgeons consider follicular-unit grafting the definitive procedure.

As discussed in Anatomy in Overview, transplanting only follicular units and dissecting away all non–hair-bearing tissue can offer several advantages. These follicular-unit grafts can be placed into tiny recipient sites, allowing for dense packing and reducing postprocedure crusting. The requirement for careful dissection reduces the accidental transection rate and therefore minimizes depletion of good hair follicles, a benefit that potentially maximizes hair yield from a particular strip of donor hairs. Finally, because hairs are transplanted in accordance with their natural growth in these tiny follicular units, the results are virtually undetectable.

The follicular units can be obtained by either the strip technique (follicular unit grafting of follicular unit strip surgery) or individual extraction (follicular unit extraction). Follicular unit extraction is preferred for younger men and those who wish to shave their head, because it avoids making a linear donor site scar.

The technique used in women differs from that used in men.[21] To prevent telogenic effluvium of the existing hairs, the use of minoxidil 2% for 2 weeks preoperatively and resuming 5-7 days postoperatively is increasing in popularity. Larger grafts behind the hairline are necessary to create increased density. Some authorities prefer the 0.5 X 2.5-mm slot graft, which contains 5-7 hairs and routine use of 3.5X loupe magnification to avoid injury to existing hairs. The grafts are cut using stereo microscopes.

To perform hair transplantations in the eyebrow, a pattern must first be made by the patient, surgeon, or esthetician. Eyebrow and eyelash transplantation require a great deal of maintenance. Brow hairs must be trained with gels or waxes, and eyelashes must be curled. Both must be trimmed and shaped. Use of donor trichophytic closure techniques can decrease visibility of donor scars.[22]

For patients with extensive alopecia or those with thin black hair and pale white scalp skin, major grafts still produce a tufted or artificial appearance. In response to these patients, in 1986, Dr Wayne Bradshaw introduced micrografting techniques that involved the use of single hairs as an alternative method of hair replacement. The demonstration of his own scalp covered with thousands of single hair grafts at a major hair transplant meeting opened up the field to procedures other than major grafts and introduced size as a major variable in hair transplant surgery.

Minigrafts and micrografts

Micrografts, which consist of 1-2 hairs per graft, and minigrafts, which contain 3-8 hairs per graft, became part of the new tools available to the hair transplant surgeon. These smaller grafts, when properly placed, provide a more natural, less abrupt appearing hairline in contrast to the standard graft of 4 mm. Nordstrom demonstrated that the smaller minigrafts and micrografts are best placed into incision sites termed "slits" placed in horizontal rows along the frontal hairline.[23] His techniques changed the mechanics, appearance, and character of the procedure.

Slit techniques supported a simpler method for placing hair grafts. Large numbers of 1- to 3-hair micrografts are placed in slit incisions without using recipient punches to remove bald scalp. The technique can be used for younger patients with thinning hair without sacrificing existing hair follicles in the recipient area. Patients with female alopecia, cicatricial alopecia, and extensive alopecia were now candidates for slit graft hair transplantation. The older concept of removing bald scalp and replacing it with hair-bearing scalp thus had changed with the addition of slit minigrafting techniques. Many transplant surgeons converted to solely minigrafting and micrografting, and the old problems with the frontal hairline and its natural refinement were solved with these techniques. Fine micrograft hairs are placed in the front line and are backed up by larger micrografts and minigrafts.

The average hair transplant patient can have the procedure completed in 2 or 3 sessions rather than 4, typical with standard grafts. Using these techniques, even poor candidates with thin dark hair can have natural, blended hairlines. Innovators such as Alfonso Barrerra have demonstrated that the "mega-session" approach allows the transplantation of thousands of micrografts and minigrafts during a single operative procedure.[24] In most cases, an additional follow-up procedure, if necessary, is usually minor and brief.

Slits and holes

The traditional harvesting technique for obtaining minigrafts and micrografts still used standard hair transplant punches. Minigrafts and micrografts were harvested from 4.5-mm standard grafts by quadrisecting them to smaller grafts. Slits or recipient holes were made with 1.5-mm and 2.0-mm trephines, placing the slits or smaller holes near the frontal hairline and the larger ones farther back. The grafts then were placed into the recipient holes where bald scalp was removed and thus treated as a standard hair transplant procedure. A major debate ensued as hair transplant surgeons arguing over which technique was better, slits or holes, for minigrafts and micrografts.[25, 26]

It was noted that the slit grafts compressed with healing to a single stalk from which 2-5 hairs would grow. This gave an artificial or tufted look when only slit minigrafts were used. The grafts did not have the natural density of holes for minigrafts. Similar minigrafts placed in holes seemed to remain spread out and did not have this compressed, artificial appearance. The advocates for holes emphasized that using the small holes to remove bald scalp was advantageous because density was greater than that obtained with slit grafting techniques alone. Others versed in both procedures have found that mixing slits with holes and varying graft size are major factors in obtaining a natural hair transplant.

Harvesting technique

There currently exist 2 methods of hair follicle harvesting: follicular unit strip surgery (or strip harvesting) and follicular unit extraction. Both possess unique advantages and disadvantages. Regardless of which method is used, the importance of extracting hair follicles from within the safe donor area remains paramount.

Extracting intact follicles from the safe donor area for subsequent transplantation ensures not only that they are the most likely to remain in their new location for the longest period of time, but also that any scar remaining in the area from which they were extracted will be concealed by neighboring hairs for the longest period of time. Maximum follicle survivability is also aided by transplanting only intact hair follicles that are not transected by traumatic extraction. To this end, with either follicular unit strip surgery or follicular unit extraction methods, the skin incisions are angled parallel to the hair follicle (rather than simply perpendicular to the scalp itself) to minimize transection.

Follicular unit strip surgery

Within the safe donor area, a strip is excised as an elongated fusiform ellipse of full-thickness scalp using either a single No. 10 or No. 15 blade or a double-bladed scalpel with blades mounted in parallel.

Prior to strip excision, the desired donor region may be infiltrated at a depth of 4-5 mm with sterile saline tumescence in order to minimize follicle transection by aligning them more perpendicularly to the skin surface and to provide separation between the follicular bed base located within the superficial subcutaneous tissue and the larger nerve plexuses and vessels that abound within the deep subcutaneous tissue.

The width of the elliptical strip (generally ranging from 10-15 mm) is determined by the laxity of the patient’s scalp in order to yield the maximum number of grafts while still limiting tension upon closing the edges of the resultant wound with either sutures or skin staples. The advantages of follicular unit strip surgery include, but are not limited to, a larger number of grafts harvested in a shorter period, lower hair follicle transection rates (2-5%), and the ability for inclusion of more protective tissue surrounding the stem cell–containing portion of the transplanted hair follicles owing to the manual dissection under microscopic visualization.[27]

Regardless of the number of sessions a patient may undergo throughout his or her lifetime, only a single scar should remain. The scar from any prior session should always be included within the subsequent strip excision.

Follicular unit extraction

Individual hair follicles or small, naturally occurring groupings of 2-4 follicles (follicular units) may be extracted either manually or with a motorized rotating punch device using follicular unit extraction. Akin to a cylindrical cookie cutter, the punch incises a 0.7- to 1.2-mm diameter circular scalp area. The punched-out follicles are then manually extracted with forceps.

Follicular unit extraction has the advantage of not creating a linear scar (resulting in a shorter, more comfortable recovery time) and allowing patients to wear their hair shorter in the donor area after the procedure.[28] However, this method may result in numerous hypopigmented punctate scars within the donor area. It may also result in increased follicle transection rates (which reduce graft hair survivability). Since follicular unit extraction is more time consuming for the patient and the physician, robotic devices also perform this method of follicle harvest.

Furthermore, as each individual follicle extracted must be separated by three or more intact neighboring follicles so as not to create a uniformly alopecic donor area, the risk of needing to harvest follicles from a larger surface area that extends beyond the limits of the safe donor area is heightened.

Over time, as the fringe hair beyond the safe donor area is lost, the punctate scars may be exposed and transplanted follicles harvested from this fringe area may disappear.

Creating and dissecting grafts (follicular unit transplantation)

After either method of harvesting (although to a much lesser extent with follicular unit extraction), the follicular units obtained must be trimmed under microscopic visualization using a razor blade.

In follicular unit transplantation, only hair follicles separated into their naturally occurring clusters of 1-4 (or more) hairs are transplanted, rather than large grafts containing multiple (3 or more) follicular units. The average naturally occurring follicular unit contains approximately 2.3 hairs.

Resultant grafts should retain a pear shape in which the epidermis has been maximally trimmed while the dermal and subcutaneous tissue surrounding the follicle isthmus and inferior portion remains.

This optimal micrograft shape is frequently achieved after follicular unit strip surgery, but rarely from follicular unit extraction. The cushioning provided by the intact surrounding tissue has been found to maximize graft viability by minimizing desiccation during preinsertion storage and mechanical trauma to the follicle from handling.[29]

Graft storage

Selection of proper storage solution has grown increasingly more important as larger surgeries involving smaller grafts have become more common and out-of-body time has lengthened. Survival of transplanted grafts has been shown to decrease about 1% per hour out of the body.[30] Factors of negative influence during this extended out-of-body time between harvest and implantation include ischemia-induced hypoxemia and subsequent adenosine triphosphate depletion, as well as ischemia-reperfusion injury. Three categories of storage media (ie, intravenous fluids, culture media, hypothermic tissue–holding solutions) help minimize out-of-body variations in pH, osmotic balance, antioxidant capabilities, and nutrient support to follicles.

Creating recipient sites

Various techniques are used to create and prepare recipient sites for subsequent transplantation of follicular units. With each method, the critical element of following the angle and direction at which the hair follicle exits the scalp results in the least damage to existing hairs and the most natural-appearing transplanted hair.

The most widely accepted density of recipient site creation distributes 30 follicular units per square centimeter. Some practitioners advocate for dense packing of more than 40 follicular units per square centimeter. However, the viability of grafts may be compromised as competition for a limited blood supply increases.

Various techniques exist for recipient site creation and graft insertion. Blades may be cut to match the size of the follicular units to be inserted. Hypodermic needles (18-21 gauge) may be used to make incisions for subsequent graft placement. Recipient site size increases as the surgeon moves posteriorly away from the hairline and the priority shifts from single, fine-caliber hairs to multiple and higher-caliber follicular units.

A stick-and-place technique can be used to virtually eliminate the time between which the recipient site is made and the graft is placed within it.

A spread-and-place technique minimizes mechanical trauma from graft handling as the graft is placed into a smaller recipient site.

Graft insertion

Jeweler forceps or similar nontoothed forceps are generally used to gently place the graphs into recipient sites. Transplanted hair follicle viability is maximized by minimizing mechanical trauma to the follicle. This is accomplished by handling the subcutaneous tissue along the base of the graft rather than the graft itself. Furthermore, some implantation devices exist that allow for near-simultaneous recipient site creation and hair follicle insertion.[31]

 

Preoperative Details

On the day of the procedure, a relaxing atmosphere should be created, enhanced by the usual administration of the chosen oral sedation. Diazepam (Valium) 10 mg and zolpidem (Ambien) 10 mg are effective and safe options.

A valuable opportunity to further discuss expectations and goals with the patient and his or her significant others is presented when marking the planned transplant areas on the patient.

An aesthetic hairline design is crucial in providing a natural-appearing result appropriate for the individual at present and in the future. Aesthetic hairline design usually requires a hairline irregular and wavy appearing, with slight-to-substantial frontotemporal recessions. In basic hairline design, the central-most aspect of the hairline is placed 8-10 cm above the nasion (root of the nose). Then, the hairline is carried laterally in an up-sloped direction when the patient is viewed on the Frankfort horizontal plane. This design results in the central aspect of the hairline being the lowest (most caudal). In many patients, the creation of a slight widow's peak improves the natural appearance.

In patients with substantial caudal recession of the superior aspect of the temporal tuft, transplanting this area to build it superiorly is sometimes helpful. Fine grafts containing 1-2 hairs are typically used to create a thin but natural-appearing result. The resulting temporal horns, which often occur naturally, allow the lateral hairline to join with the superior temporal hairline, even if the transplanted hairline is high and thus prevents an isolated frontal tuft.

Note that all lines drawn to mark the hairline serve as a rough template, from which an irregular saw-tooth pattern can be transplanted to mimic natural hairlines. The goal of hairline creation is to create a hairline that is not discernible as a line.

A conservative approach is important when transplants are placed into the crown region because of the likelihood of progressive enlargement of the crown. If this occurs, additional grafting is required in the future to avoid the appearance of a donut-shaped area of bald scalp surrounding a central circle of transplanted hairs. Frequently, only the anterior one half to two thirds of the crown is transplanted densely, whereas the remaining crown area is transplanted less densely by scattering 1- or 2-hair micrografts to provide some minimal coverage to prevent the appearance of a shiny area.

The final step before the patient is transferred into the procedure room is to determine the necessary size of the donor area and then to trim the hairs to be transplanted. The donor site is usually in the middle-to-superior aspect of the back of the head, accounting for and avoiding any potential recession in the crown area. A number of techniques have been described to determine the size of donor area necessary to provide the required number of grafts. Typical procedures consist of 1400-2800 follicular-unit grafts, but procedures as large as 3200 grafts are not uncommon. Use of a densitometer, which measures the number of hairs per square centimeter, is the most accurate way to determine donor-site size. Approximately 75 follicular units are obtained from each square centimeter of area; therefore, a planned 2000-graft procedure requires a donor strip 24 X 1 cm.

See the images below.

Case 1. Views before and 6 months after a procedur Case 1. Views before and 6 months after a procedure performed by using 2000 follicular-unit micrografts.
Case 1. Close-up view of the hairline of a patient Case 1. Close-up view of the hairline of a patient 6 months after a procedure performed by using 2000 follicular-unit micrografts.
Case 2. Views before and after 3500 follicular-uni Case 2. Views before and after 3500 follicular-unit micrografts performed in 2 procedures.
Case 2. Close-up view of the hairline of a patient Case 2. Close-up view of the hairline of a patient after transplantation of 3500 follicular-unit micrografts performed in 2 procedures.

The patient should be free of all medications that may influence bleeding tendency such as aspirin, nonsteroidal anti-inflammatory medications, blood thinners, and herbs or nutrients that create bleeding problems such as garlic, St Johns wort, and Ginkgo biloba. The patient may have a light meal prior to surgery and be given oral fluids as needed

Patients are advised to wash their hair with shampoo on the evening prior or morning of the surgery. Once the region within the safe donor area (the region within the inferior parietal and inferoposterior scalp in which hair follicles are most likely to remain throughout a patient’s lifetime[32] ) has been determined, the hair within that region should be clipped to approximately 1-2 mm in length with either scissors or an electric trimmer.

The donor area and recipient area into which the grafts will be placed should be prepped with a povidone-iodine antiseptic solution. However, scrubbing the recipient and donor areas with 4% chlorhexidine gluconate may be preferable in patients with white or grey hair as the povidone-iodine may temporarily stain light-colored follicles.

The use of perioperative antibiotics remains controversial in hair restoration surgery. The decreased risk of wound infection must be weighed against the increased threat of hypersensitivity reaction and the possible emergence of resistant organisms. Prophylactic antibiotic use is most effective when administered 1 hour preoperatively and is not questioned in instances of endocarditis prophylaxis or other precautionary uses. First-generation cephalosporins are most commonly used preoperatively. When hypersensitivity exists, erythromycin is an effective alternative. These prophylactic oral regimens coupled with topical antibiotic use along the donor wound postoperatively help reduce the already slim risk of infection. Some practices advise patients to continue use of oral and topical antibiotics for 3-5 days postoperatively.

Patient Preparation

Anesthesia

Preoperative analgesic and antianxiolytic medications are often given to patients in oral form prior to the surgery and intravenously throughout the procedure. In addition, local anesthesia is administered slowly and using a fine 30-gauge needle in order to minimize discomfort. Local administration of 1-2% lidocaine with 1:100,000 epinephrine along the inferior edge of the clipped donor area provides ample anesthesia while minimizing intraoperative donor wound bleeding. Local infiltration to create a ring block of anesthesia anterior to the anticipated recipient area remains the most commonly used technique for achieving recipient region anesthesia. Care should be taken in both the donor and recipient areas to limit the lidocaine dose to 7 mg/kg with epinephrine (maximum 500 mg) or 4.5 mg/kg without epinephrine (maximum 300 mg). After 2 hours, the local anesthetic should be reinforced with 0.25%-0.5% bupivacaine with 1:100,000 epinephrine (maximum 200 mg). This lasts approximately 4 hours.

Positioning

The patient should be placed either in a prone position or (less often) a seated position for donor hair follicle removal.

Intraoperative Details

The patient is seated in a semirecumbent position, and local anesthetic is injected. A computerized injection device called the Wand, which allows for the slow and controlled injection of agent, can be used. First, the donor area is injected superficially, followed by a slightly deep injection along the entire hairline to create a field anesthesia. Most patients receive oral sedation, whereas local anesthetic is sufficient for the rest. The rare patient chooses to have intravenous sedation provided by a nurse anesthetist. With the patient sitting, the scalp is prepared in sterile fashion. Approximately 25 mL of 1:50,000 epinephrine is injected into the donor region for tumescence. The single fusiform donor strip is most easily excised in a superficial subcutaneous plane, which helps in avoiding the occipital neurovascular bundle structures and other smaller vessels. If necessary, electrocautery is used, and the donor-site incision is reapproximated with a simple running 3-0 Prolene suture by staying superficial to the hair follicles to minimize compression injury and resultant alopecia along the donor-site scar.

At this point, the surgical personnel split into two teams. Good results in hair transplantation require a highly trained team of assistants to dissect grafts and to help plant them. One team consists of those who perform the slivering; this team sections the donor strip into many narrow strips that are 1 follicular unit wide. These narrow strips then can be divided into individual grafts consisting of a single follicular unit. These follicular units most commonly contain 2-3 hairs, but they can contain 1-4 hairs. Excess tissue not containing hair is excised to allow for the transplantation of just these follicular units.

Assistants perform graft cutting with the aide of binocular microscopes for most accurate dissection. This process is demanding and time consuming but critical for the success of the procedure. The typical assistant can cut 100 grafts per hour; hence, a team of 6 assistants can cut 1800 grafts in 3 hours. The grafts are cut on a Teflon cutting block by using Personna size-11 scalpel blades or double-sided razor blades. While awaiting transplantation, the grafts are stored in chilled preservative-free solution of isotonic or some other storage solution. If the follicular unit extraction technique is to be used, the patient is usually placed in a face-down fashion and the back of the head prepared by shaving it then anesthetizing. Using a variety of extraction tools, including individual manual punches 0.9-1 mm in size, a hand-held specially designed drill, or more recently one of several automated devices, the individual follicular units are harvested. From several hundred to 1800 or more grafts can be obtained. These grafts are placed into a storage solution where they await transplantation.

As grafts undergo dissection, the surgeon creates recipient sites. The author's preferred instruments are tiny blades custom cut from single-edge Personna razor blades. These blades measure 0.5-0.9 mm, but blades of 0.6, 0.7, and 0.8 mm are most commonly used for grafts containing 1, 2, and 3 hairs, respectively. The 0.6-mm blade is typically used along the frontal hairline, where 1-hair grafts are placed most anteriorly, with the 2-hair grafts placed immediately behind into incisions made with a 0.6- or 0.7-mm blade. Finally, depending on the size of the 3- and occasional 4-hair grafts, the 0.8- or 0.9-mm blade is used to create the remainder of recipient sites.

Several concepts are important in the making of recipient sites, as the direction and location of these sites determine the direction and location of growth of the transplanted hairs. Usually, the more anterior along the hairline, the more oblique the angle of penetration of the recipient site. By working posteriorly, a continued anterior but less oblique direction of growth is maintained. When hairs are transplanted into thinning areas that still have original hairs, the direction of the recipient sites must mirror the direction of growth of these existing hairs to prevent transecting and damaging the hair follicles and to ensure an even and equivalently patterned growth of all scalp hairs. These recipient sites must be made between existing hairs to avoid transection of existing hair follicles. Although this process is a time-consuming challenge, such attention to detail reduces telogen effluvium (ie, rapid hair loss), which is observed when a substantial number of hairs are damaged.

In the crown area, the radial direction of growth of hairs is maintained. In the anterior portion of the crown, the hairs tend to grow anteriorly, while more posteriorly, the hairs indeed grow posteriorly. Somewhere between the anterior and posterior areas usually lies a circular whirl. On occasion, recreation of this whirl is necessary, especially when the entire crown is filled.

After the recipient sites have been created, the grafts are then inserted. This is an extremely challenging and delicate process because atraumatic placement of individual grafts is crucial to prevent lack of growth of the hairs and to minimize scalp edema. For graft insertion, the preferred tool is the curved and straight ultrafine jewelers' forceps. These forceps allow grafts to be handled and placed by grasping them only along the subcutaneous fat just deep to the follicle.

Postoperative Details

Graft placement constitutes the final step in the time-consuming hair-transplant procedure. A 2200–follicular-unit graft procedure typically requires 5 hours to perform when done by a surgeon and 8 assistants). Afterward, patients can leave the office bandage free. To prevent any periorbital swelling that sometimes results from edema along the frontal hairline from migrating inferiorly, a strip of elastic tape is placed across the patient's forehead. This tape is worn for the next 3 days and is easily concealed by wearing a baseball hat.

On postoperative day 1, patients usually return to the office for a hair wash and checkup. The occasional "popped" graft can be returned to the recipient site at this time. On postoperative day 3, patients can wash the hair themselves by gently applying shampoo and rinsing with water. Sutures are usually removed on days 10-12. By this time, all crusting (typically minimal with the follicular unit grafting procedure) should be gone, and the scalp typically appears entirely normal except for possible slight erythema along the recipient site region. To speed the resolution of crusting and to promote rapid healing, patients can use a copper-containing moisturizing spray called GraftCyte. Postprocedural medications include cephalexin 500 mg for 3 days, prednisone 50 mg for 3 days, and ibuprofen or acetaminophen with codeine #3 as necessary. For most patients, discomfort is mild, and ibuprofen is adequate.

Many practices use a postoperative compression surgical dressing to minimize local edema and to reduce the risk of graft dislodgement. Prior to positioning this dressing, surgeons should apply a topical antibiotic ointment, nonstick gauze, Kerlix gauze, and wrapped gauze to establish a turban-like pressure dressing. This dressing is removed on postoperative day 1 when the patient is given instructions related to scalp care.

Corticosteroids may be administered orally (up to 60 mg) followed by a tapered dose in order to reduce postoperative facial edema as well as donor area discomfort. If an intravenous line is established, dexamethasone may be given in doses totaling 12 mg during the procedure. Some surgeons also recommend local administration of triamcinolone acetonide 2.5 mg/mL in 0.5% bupivacaine along the inferior donor wound edge or anterior to recipient site created along the hairline to minimize postoperative edema.[33]

Patients may experience postoperative discomfort along the donor wound edge. Typically, this is minimal and lasts only overnight. However, as this discomfort may correspond with edema along the suture line, some patients may require oral narcotics, especially if the pain persists for more than a day or two (rare). Generally, acetaminophen with codeine, hydrocodone bitartrate 5 mg/acetaminophen 500 mg (Vicodin), or oxycodone 5 mg/acetaminophen 325 mg (Percocet) are more than sufficient to alleviate postoperative discomfort.

Activity

After the procedure, advise patients to avoid exertion for the first 48 hours. After this, light exercise, such as running and golf, can be resumed. By postoperative day 5 when the transplanted follicles have established their own capillary network, no further restrictions are placed on the patient with the exception of swimming with the head submerged, which should be delayed until postoperative day 7.

Long-Term Monitoring

Advise patients that more than 80% of transplanted hairs fall out between postoperative days 14 and 21. With follicular-unit grafting, as many as 20% of hairs may continue to grow. The transplanted hairs reappear 3-4 months later and continue to grow for the patient's lifetime at a rate of approximately 0.5 in/month. To shorten this interval of hair regrowth to 10 weeks, patients are instructed to apply minoxidil daily for the first 3 months.

Approximately 50% of patients choose to undergo a second hair-transplant procedure at some point. This procedure can be performed as soon as 5 months after the first procedure. The most common reasons for patients wanting a second procedure are to increase hair density and to cover more areas than could be covered in the initial procedure. Patients sometimes return several years later to have an additional procedure or to fill in areas that have undergone hair loss. With additional procedures, the donor site almost always encompasses the first procedure's donor site, resulting in a continued single incision line and minimal scarring.

 

Medication

Medication Summary

The two medications that have received approval from the US Food and Drug Administration (FDA) for treating hair loss are minoxidil and finasteride. Minoxidil (Rogaine) is a liquid applied directly to areas of the scalp undergoing hair loss. Finasteride is a pill taken orally once per day.

While perioperative antibiotic use remains controversial in hair restoration surgery, some suggest that a first-generation cephalosporin such as cephalexin may be appropriate, with erythromycin being an effective alternative.

Oral sedation for the procedure can include medications such as diazepam and zolpidem. Anesthetic agents for the procedure include lidocaine, bupivacaine, and epinephrine.

Postprocedure pain-control agents can include ibuprofen, acetaminophen with codeine, hydrocodone bitartrate 5 mg/acetaminophen 500 mg, and oxycodone 5 mg/acetaminophen 325 mg, although typically only ibuprofen is needed. Additionally, some suggest prednisone helps reduce postoperative facial swelling and helps with discomfort.

Analgesics-Antipyretics

Class Summary

Pain control is essential to quality patient care. Analgesics ensure patient comfort, promote pulmonary toilet, and have sedating properties beneficial to patients who experience pain.

Acetaminophen (Tylenol, Aspirin Free Anacin, APAP 500, Acephen, Cetafen)

This is the drug of choice for treating pain in patients with documented hypersensitivity to aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs), who are diagnosed with upper gastrointestinal disease, or who take oral anticoagulants.

Codeine/acetaminophen (Tylenol #3, Tylenol #4, Tylenol with Codeine)

Acetaminophen and codeine combination is used for the treatment of mild to moderate pain.

Hydrocodone/acetaminophen (Anexsia, Hycet, Lorcet)

This combination is used for the relief of moderate to severe pain.

Oxycodone/acetaminophen (Endocet, Percocet, Primlev)

The combination of oxycodone and acetaminophen is used for the relief of moderate to severe pain. It is the drug of choice for aspirin-hypersensitive patients.

Ibuprofen (Addaprin, Advil, Motrin, Caldolor, Dyspel)

Ibuprofen is usually the drug of choice for treating mild to moderate pain, if no contraindications exist. It is one of the few NSAIDs indicated for fever reduction.

Naproxen (Aleve, Anaprox, Anaprox DS)

Naproxen is used for the relief of mild to moderate pain. It inhibits inflammatory reactions and pain by decreasing cyclooxygenase (COX) activity, which results in decreased prostaglandin synthesis.

Ketoprofen (Nexcede)

Ketoprofen is used for relief of mild to moderate pain and inflammation. Small dosages are indicated initially in small patients, elderly patients, and patients with renal or liver disease. Doses higher than 75 mg do not increase the therapeutic effects. Administer high doses with caution, and closely observe the patient’s response.

Antianxiety Agents

Class Summary

These agents are used to reduce anxiety.

Diazepam (Diastat, Diastat AcuDial, Valium)

Diazepam modulates the postsynaptic effects of gamma-aminobutyric acid–A (GABA-A) transmission, resulting in an increase in presynaptic inhibition. It appears to act on part of the limbic system, the thalamus, and the hypothalamus, to induce a calming effect. It also has been found to be an effective adjunct for the relief of skeletal muscle spasm caused by upper motor neuron disorders.

Diazepam rapidly distributes to other body fat stores. Twenty minutes after initial intravenous infusion, the serum concentration drops to 20% of maximum plasma concentration (Cmax). Individualize the dosage and increase cautiously to avoid adverse effects.

Sedative/Hypnotics

Class Summary

Sedative and hypnotic agents are used to induce sleep and sedation.

Zolpidem (Ambien, Ambien CR, Edluar)

Zolpidem increases neural hyperpolarization by enhancing the activity of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) through selective agonist activity at the benzodiazepine-1 receptor.

Topical Skin Products

Class Summary

Agents that increase cutaneous blood flow may stimulate healthy hair follicles.

Minoxidil topical (Rogaine)

Minoxidil may stimulate hair growth secondary to vasodilation, which increases cutaneous blood flow and, in turn, stimulates resting hair follicles.

5-Alpha-Reductase Inhibitors

Class Summary

Agents in this class inhibit the conversion of testosterone to dihydrotestosterone, which, in turn, significantly reduces dihydrotestosterone levels.

Finasteride (Propecia, Proscar)

Finasteride is a 5-alpha-reductase inhibitor that is approved for use in benign prostatic hypertrophy and in male-patterned alopecia. It blocks conversion of testosterone to its more active metabolite, dihydrotestosterone.

Local Anesthetics

Class Summary

Local anesthetic agents are used to increase patient comfort during the procedure.

Lidocaine anesthetic (Xylocaine, Zingo)

Lidocaine is an amide local anesthetic used in a 1-2% concentration in combination. This agent inhibits depolarization of type C sensory neurons by blocking sodium channels. It can be used in a formulation with epinephrine, which prolongs the duration of the anesthetic effects from lidocaine by causing vasoconstriction of the blood vessels surrounding the nerve axons.

Bupivacaine (Marcaine, Sensorcaine)

Bupivacaine 0.25-0.5% with or without epinephrine may be used. It decreases permeability to sodium ions in neuronal membranes. This results in the inhibition of depolarization, blocking the transmission of nerve impulses. It can be used in a formulation with epinephrine, which prolongs the duration of the anesthetic effects from bupivacaine by causing vasoconstriction of the blood vessels surrounding the nerve axons.

Corticosteroids

Class Summary

Corticosteroid agents have both anti-inflammatory and salt-retaining properties. Glucocorticoids have profound and varied metabolic effects. In addition, these agents modify the body's immune response to diverse stimuli.

Triamcinolone topical (Kenalog Orabase, Kenalog topical, Pediaderm TA)

Triamcinolone can be used topically. It decreases inflammation by suppressing the migration of polymorphonuclear (PMN) leukocytes and reversing capillary permeability.

Dexamethasone (Baycadron, Decadron, Dexamethasone Intensol)

Dexamethasone has many pharmacologic benefits, but also significant adverse effects. It stabilizes cell and lysosomal membranes, increases surfactant synthesis, increases serum vitamin A concentrations, and inhibits prostaglandin and proinflammatory cytokines.

Prednisone (Deltasone, Prednisone Intensol, Rayos)

Prednisone may decrease inflammation by reversing increased capillary permeability and suppressing PMN leukocyte activity. It may be beneficial to use intravenous (IV) pulses; this may be associated with a lower frequency of calcinosis.

Prednisolone (FloPred, Millipred, Millipred DP)

Corticosteroids may decrease inflammation by reversing increased capillary permeability and suppressing PMN leukocyte activity.

Antibiotics

Class Summary

Empiric antimicrobial therapy must be comprehensive and cover all likely pathogens in the context of this clinical setting.

Erythromycin ethylsuccinate (E.E.S., EryPed)

Erythromycin is a macrolide used for penicillin-allergic individuals. It inhibits bacterial growth, possibly by blocking dissociation of peptidyl transfer ribonucleic acid (t-RNA) from ribosomes, causing RNA-dependent protein synthesis to arrest. Erythromycin is administered for the treatment of staphylococcal and streptococcal infections.

In children, age, weight, and severity of infection determine proper dosage. When twice-daily dosing is desired, half of the total daily dose may be taken every 12 hours. For more severe infections, double the dose.

Cephalexin (Keflex, Panixine Disperdose)

Cephalexin is a first-generation cephalosporin that inhibits bacterial growth by inhibiting bacterial cell wall synthesis. This agent is bactericidal and is effective against rapidly growing organisms forming cell walls. Cephalexin is an acceptable alternative to penicillin and may be useful in patients with minor penicillin allergies.