A chronic scarring folliculitis that mainly affects young black men. The lesions are localized on the neck and occipital scalp. The condition can be treated with corticosteroids either alone or in combination with antibiotics. Surgery is the treatment of choice in patients with very extensive keloidal plaques. Hair transplantation is not recommended.

The medical term for hair loss. There are numerous types of alopecia. Alopecia can be classified as diffused or localized, and by presence or absence of scarring. The most common form of surgically treatable alopecia is androgenic alopecia (AGA).

A common non-scarring alopecia. Although the exact pathophysiology of AA is not clear, it has been determined that it is a T-lymphocyte mediated autoimmune condition that occurs in genetically susceptible individuals. It typically presents itself with sharply demarcated coin-sized patches of alopecia. The scalp is the most commonly affected area, but any hair-bearing area can be involved. Spontaneous remissions and reoccurrences are common. Available treatment options are neither curative nor preventative.

A surgical procedure that entails the removal of a strip of balding upper scalp in the crown and vertex areas. The natural flexibility of the scalp is used to stretch the surrounding hairy scalp into place.

A loss of all hair on the scalp.

A loss of all hair on the body.

A vaso-dilatator chemically similar to minoxidil. Studies providing evidence of its efficacy are absent, but it is claimed to be effective in the deduction of telogen hair with anagens inducible activity and prolonged hair follicle age as well.

The active growing phase of the hair that lasts between 2 to 6 years. An increase in the duration of anagen does not alter the hair fiber density over the scalp. Instead, it determines to what length the hair can grow. Anagen can be shortened in androgenetic alopecia.

Defines the structures that impede the extraction of the follicular group from the surrounding tissue. The follicular adherence includes the sebaceous gland and the ion of the arrector pili muscle, the attachment of the dermis, and the connections between the connective tissue sheath and the surrounding adipose tissue.

Any natural or synthetic compound that stimulates or controls the development and maintenance of male characteristics.

A heritable androgen and age-dependent process resulting in a progressive decline in visible scalp hair density in a sex-dependent defined pattern.

The anterior border of the temporal area of hair that falls inferiorly and vertically from the most posterior limits of the fronto-temporal recessions to a point approximately level with the external auditory meatus.

An agent that blocks the action of androgens.

A tiny smooth muscle that connects the hair follicle with the dermis.

A piece of tissue surgically removed for microscopic examination.

Donor follicles that are harvested from any region of the body except the traditional scalp donor area. Body hair includes all hair inferior to and inclusive of the neck and beard. Body hair has an unpredictable and variable yield.

The lowermost portion of the hair follicle containing rapid proliferating matrix cells that produce the hair.

The convex protrusion of the outer root sheath in the most distal permanent hair follicle stem cells.

It appears to increase the microcirculation in the skin. It was shown to stimulate hair growth in vitro.

An average number of hairs in each follicular unit. It is determined by dividing the number of hairs present in 1cm2 by the number of follicular units observed in the same square centimeters.

Camouflaging agents reduce the color contrast between the hair color and the color of the scalp. They produce an overall perception of increased hair density. Hair fibers, powder cakes, scalp lotions, scalp sprays and hair crayons are scalp-camouflaging agents.

The catagen phase is a brief transitional phase between anagen and telogen that lasts only a few weeks.

A form of scarring alopecia. It mostly affects African-American females. Hair loss usually begins at the vertex and expands outward symmetrically, eventually affecting the entire scalp. The cause of CCCA remains unclear. Topical corticosteroids and im- munomodulators, oral antibiotics, intralesional injections of corticosteroids, and short courses of oral corticosteroids are available options for patients.

Frontal midline recession with the thinning and widening of the central part of the scalp without diffused hair loss.

Uncommon and clinically diverse disorders that result in permanent and irreversible loss of scalp hair. These disorders may be primary, with the follicle itself being the target of the disease process, or secondary, where hair follicles are destroyed as part of a more generalized tissue-damaging event (e.g. deep skin infection, thermal burn, trauma, or ionizing radiation). Clinically it is characterized by the disappearance of visible follicular ostia within an area of alopecia.

The cobblestoned appearance of the scalp that occurs due to the placement of the graft in too high a position relative to the surrounding scalp.

An index that adapts to an infinite number of density and distribution patterns (male and female) and uses numbers instead of words to identify the topography of the scalp. Hair loss is scored with a single number from 1 to 100 and is designated by the hair loss index. The distribution of hair loss is displayed on a simple bar graph and called the hair loss profile

The outermost layer of the hair shaft

An androgen receptor antagonist and progestin. It should only be used in women.

There is no established definition of dense packing. For many surgeons, dense packing is defined as placing hair grafts at a rate higher than 30 grafts per square centimeter in the recipient area. Forty to fifty grafts per square centimeter are fairly common. The aim is to produce more even, consistent and natural looking hair.

A tool that gives a rapid, accurate and reproducible assessment of donor hair density.

Analyzes the scalp under high-power magnification to give information on hair density, follicular unit composition and degree of miniaturization.

The number of hairs in a specific area.

Refers to the utilization of different accessories on or around the punch to precisely control the depth to which the punch can be ed.

A condensate of specialized mesenchymal cells with important inductive properties that is situated at the base of the hair follicle. The dermal papilla contains nerves and blood vessels that supply glucose for energy and amino acids to make keratin. The dermal papilla determines the size of the hair bulb and the hair shaft produced. It is likely the target of androgen-mediated events leading to miniaturizations and hair-cycle changes.

An inflammatory condition of the skin.

The term used to describe diffused hair loss that involves thinning. The occipital donor area is spared.

The term used to describe general thinning across the entire scalp.

The most potent natural androgen in humans. Testosterone is converted to DHT by the enzyme 5-alpha reductase. It is believed that DHT is the key androgen required for the induction of MPHL.

Discoid lupus is an autoimmune disease limited to the skin. DLE often leads to local areas of scarring and permanent localized hair loss. First-line treatment options include topical and intralesional steroids, hydroxychloroquine, and sun protection.

The fringe above the ears and around the back of the head where hair follicles are genetically programmed to remain intact and grow throughout life.

The number of hairs in the donor area measured per square centimeter. In general, patients require a donor density of at least 40 FU/cm2 to be considered for transplants.

The concept that hair follicles transplanted from the donor area will continue to grow in the recipient area.

Tension may be applied to the donor area to stabilize the fluidity of the tissue through a variety of means including the following: tumescence, clamps, or manual or stretching forces applied through other means such as tensioners or stapling a latex material from one side of the scalp to the other.

A form of alopecia usually presented as a diffused, non-scarring variety most commonly involving the scalp. In almost all cases, there is recovery of hair loss after the discontinuation of the medication.

An inhibitor of both type I and type II 5a-reductase that was approved by the FDA for the treatment of benign prostatic hyperplasia. Dutasteride has been shown to significantly increase hair counts and hair weight, improve the ratio of anagen and telogen hairs and improve scalp coverage.

The ion of an unsharpened punch along the course of the follicle to facilitate its extraction.

The abnormal accumulation of fluid in the space between tissues.

Active hair loss denoted by the hair loss of > 100 hairs daily over a longer time period of 2/4 weeks.

The outer protective, nonvascular layer of the skin

The release of telogen fibers from the hair follicles.

An action that details how a graft is divided under the microscope into singles or groups that contain fewer follicles than the original intact group, for example, those to be used in or near the front hairline.

The most common cause of alopecia in women. It presents itself with diffused non-scarring loss of hair and prominent thinning over the frontal, central, and parietal scalp. The frontal hairline is characteristically retained. The relationship between FPHL etiology and androgen or androgen receptor (AR) is less clear. Efforts to treat FPHL have mixed success and do not accomplish complete regrowth. Hair transplant surgery is emerging as an important option for patients with FPHL.

A topical cream that blocks AR in the hair follicles. Fluridil has been widely used in Europe, but is still awaiting FDA approval. It has been found to be safe for the treatment of pattern hair loss in men and women.

The physical movement of the follicle in reaction to the forces that result from the physical process of follicular unit extraction.

An implantation where dermal papilla cells are taken from a few follicles and expanded in cultures, then implanted into the skin to induce the formation of many new follicles. In the future, FCI will offer a relatively minimally invasive treatment option for hair loss.

(See Central Centrifugal Cicatricial Alopecia)

A term that refers to the number of follicular units per square centimeter.

Defined as clusters of hair in the scalp that exit the skin in close proximity to one other and that is separated by a gap from other clusters of hair. The follicular group may consist of more than one follicular unit in a tightly packed distribution on the surface of the skin.

The placing of two follicular unit grafts into one recipient site.

The majority of human hair shafts that emerge from the scalp as single, 2, and 3-hair groupings. These are the visible superficial portion of a distinctive histologic structure known as the follicular unit The follicular unit consists of one to four, and occasionally five terminal hair follicles, one, or rarely two vellus follicles, the associated sebaceous lobules, the ions of the arrector pili muscles, its neural and vascular plexuses and the fine adventitial collagen that surrounds and defines the unit.

A technique in which naturally occurring, individual follicular units are dissected from donor tissue that has been removed as a single strip. Stereo-microscopic dissection is required.

A method of graft harvest whereby punches of various types are used to remove follicular units from the donor region one at a time.

A graft consisting of a single follicular unit.

A method by which large numbers of follicular units are harvested from the donor site (usually in a long strip or ellipse) and then microscopically dissected into grafts containing single follicular units.

A form of scarring alopecia that can present itself in the vertex area. It predominantly occurs in young and middle-aged adults. The exact cause is unknown. It can be very aggressive and resistant to therapy. Treatment involves topical and oral antibiotics as well as the antineutrophilic agent, dapsone.

The scalp area that lies between the anterior hairline and a line initially drawn vertically from the left and right tragus and that then gently curve anteriorly.

A condition accepted as a variant of lichen planopilaris. It presents itself with a recession of the hairline along the sideburns and central scalp. It also affects the eyebrows and is more common in postmenopausal women. The treatment involves the use of topical, intralesional and systemic anti-inflammatory treatments.

A natural (or transplanted) zone of hair in the anterior aspect of the scalp that is separated from the adjacent fringe hair by an alley of alopecia or thinning hair.

The relatively narrow zone of hair that juts out from the posterior aspect of the frontal area or a mid-parietal bridge and that has on each side, a wide and deep fronto-temporal recession.

The non-hair-bearing skin that lies between the superior antero-temporal hairline and the lateral border of the frontal hairline.

A method of hair restoration surgery whereby parallel incisions are made in the donor scalp area to remove a strip. The length and width of the excision depend on the amount of grafts. From this strip, individual follicular units are then dissected under the stereo microscope.

The layer of the scalp that lies in between the subcutaneous tissue and the loose connective tissue.

The numerous techniques and instruments that are available for graft placement. The fundamental principles of this aspect of the procedure include gentle grasping of the grafts, maintenance of graft hydration, placement of grafts in the identical angle of site creation and also maintaining appropriate rotation of the natural curvature of the hair graft.

Hair itself has few physical functions but they include defense against the effects of UV radiation, suppression of heat loss and tactile sensation. The various hair types consist of terminal, intermediate, and vellus hairs. Hair has two separate structures: the follicle in the skin and the hair shaft that is visible on the body surface.

Any external hair-bearing device that is added to existing hair or scalp to give the appearance of a fuller head of hair, i.e.: hair weaves, hair extensions, hair pieces, toupees, non-surgical hair replacements, partial hair prostheses, hair wefts, etc. Devices may consist of human hair, synthetic fiber or a combination of both.

The tubular connection between the epidermal surface and the most distal part of the inner root sheath containing the hair shaft.

The combination of hair follicle density per unit area of skin with average hair fiber thickness. Improvements in both terminal hair density and average hair diameter work synergistically.

The growth cycle of the hair follicle. The cyclic activity of the hair follicle requires the regeneration and new assembly of its non-permanent portion during each new hair cycle. On average, the amount of new scalp hair formation matches the amount that is shed, thereby maintaining a consistent covering. Changes in hair growth cycling elicit a hair disorder. There are 3 main phases of the hair follicle cycle: an active growth phase called anagen; catagen when the hair follicle regresses; and telogen, when the hair follicle is largely quiescent. Two additional stages of the hair cycle have been described as; exogen (the release of telogen fibers from the hair follicles) and kenogen (the lag in time between the exogen and new anagen fiber development). The length of time each phase takes partly depends on the type of hair follicle involved and its geographic .

A product of the concentration of hairs and the size or caliber of each individual hair.

A theory that states only a limited or decreasing supply of hair exists, but the demand for hair increases as balding patterns develop.

The most visible product of the hair follicle. It is formed of keratin proteins.

Techniques used to rotate large portions of hair from the sides and back of the scalp to the front and central areas of the head.

A strand of hair and its root that is extracted from the donor area and transplanted into the recipient area during hair restoration surgery.

Hair follicles that have been harvested from the donor area and are ready for transplantation into the recipient area of the scalp.

A quantity that reflects the cross-sectional area of all hairs that emerge from 1 square centimeters of the scalp surface.

The method for assessing the hair bulbs and shafts using light microscopy.

A term typically used to describe the large round grafts that were used more commonly years ago.

The part of the hair follicle that exits the epidermis. It consists of three layers: the medulla, the cortex, and the cuticle.

Custom-made real hair to cover the entire scalp.

A surgical technique that transfers hair follicles from the donor area to the recipient area. The hair transplantation process consists of two parts: 1) removing the donor follicles and 2) placing them back into the skin.

A measurement of hair density that incorporates both the number of hairs per square centimeter and the hair shaft diameter.

An instrument that was designed to precisely and accurately measure hair loss, growth and breakage on any area of the scalp. It gives reproducible cross-sectional trichometry measurements. Other benefits of using the device include assessing the stability of hair loss in patients, quantifying their improvement in density over time, and also using a measuring device in clinical trials.

The first genetic test developed for predicting the risk of pattern hair loss.

A prominent part of the largest visible feature of the face. Creating a natural hairline is one of the most important elements of a successful hair transplant. The goal is to achieve the age-appropriate look that will sustain a natural appearance with the future progression of hair loss.

Refers to the use of a variety of newer, more delicate grafting techniques to alter, camouflage or soften the results of older hair transplant techniques.

The term used to describe removing hair from the donor area.

That which occurs in laboratory apparatus.

The protective response of the tissues of the body to irritationor injury.

The most proximal part of the hair follicle relative to the epidermis that extends from the sebaceous duct to the epidermal surface.

A multi-layered, rigid tube composed of terminally differentiated hair follicle keratinocytes surrounded by the outer root sheath.

That which occurs in a living organism.

The middle part of the hair follicle extending from the sebaceous duct to the bulge.

A flap that is used to reconstruct the hairline and mid-scalp. The flap has fallen out of favor today.

An overgrowth of scar tissue at the site of a wound in the skin.

An anti-fungal agent. It is used topically for the treatment of seborrheic dermatitis and dandruff and is believed to stimulate hair growth. The mechanism may involve the inhibition of inflammation or the anti-androgenic properties of the agent.

Fine hair on the body of the fetus usually shed in utero or within weeks after birth.

Incisions made perpendicular to the direction of hair growth. The lateral slit technique gives the hair restoration surgeon the ability to control the angle, direction and orientation of the transplanted hair.

An autoimmune disorder that causes a permanent scarring alopecia. Adult women make up the majority of the LPP patient population. It is the most common primary cicatricial alopecia and results in a shiny alopecia of the mid-scalp, vertex, or parietal areas. According to the severity of disease, treatment options include corticosteroids, hydroxychloroquine and immunomodulating agents.

Oxygen and glucose are required for the production of ATP, the cell's primary fuel. One method to replace graft oxygen needs that may not be fully met by the patients vascular beds, is to use postoperative liposomal adenosine triphosphate (ATP). Use of liposomal ATP was shown to enhance graft survival and graft quality when used as an additive to the holding solution and as a post-operative spray.

A disorder predominantly diagnosed in children, often receding with age.

A technique used in the treatment of AGA. Several types of products using LLLT are available for the adjunctive treatment of AGA. LLLT, particularly 650, 900 nm wavelength at 5 mW, may be an effective alternative treatment for AGA patients.

The scale for describing a type of female pattern hair loss in which there is centralized diffused loss of hair. The Ludwig I scale demonstrates mild hair thinning throughout the central scalp. The Ludwig II scale exhibits moderate with notable thinning in the central scalp. The Ludwig III scale shows severe hair loss and thinning in the central scalp.

Refers to transplanting a large number of follicular unit grafts in a single session. Megasessions are capable of treating a significant area of the scalp in one session.

A substance secreted by the pineal gland that regulates the sleep cycle. It has been known to modulate hair growth, pigmentation and molting in many species including humans. Topical application of melatonin 0.1 % solution was shown to significantly increase anagen hair.

Mesotherapy consists of superficial scalp injections of pharmaceuticals and vitamin compounds that have been previously been used to treat hair loss via the topical or systemic routes of administration.

The scalp area that lies immediately posterior to the front and extends to the vertex (crown). It is bound laterally by the temporal/parietal fringes.

A graft containing three or four hairs (small mini-graft) or five or six hairs (large mini-graft). There are many variations of mini-grafts derived from round grafts.

A primary pathological process in androgenetic alopecia resulting in the conversion of large (terminal) hairs into small (vellus) hairs. Miniaturized follicles still have the capacity to produce hairs and retain cycling ability.

Originally developed as an antihypertensive agent, it was approved by the FDA for treatment of MPHL as a 2% and 5% scalp lotion. The action mechanism of minoxidil on hair growth is still unclear. Recent studies suggest that it also enhances hair growth by increasing the production of prostaglandin E2. Topically applied, minoxidil increases hair weight with a less dramatic increase in hair counts. Adverse effects of minoxidil include skin irritation, hypertrichosis on the face and hands and tachycardia.

Hair transplantation using multi-unit grafts. In practice, these grafts may be placed into small round holes, slots, or slits.

Grafts that contain two or more follicular units in a single graft. This term replaces the older mini-graft. In practice today, MUGs contain 2-6 follicular units per graft.

Nanofibers are an ultra-fine micro-fiber hair camouflage product made entirely of natural keratin. They work by binding electrostatically charged microscopic hair fibers to each of the individual hairs to create a fuller looking head of hair.

The superior border of the occipital area of permanent hair that surrounds the alopecic or thinning vertex.

The rotation of the punch back and forth through different arcs and repetitions per minute (RPMs) during penetration. This may be done by hand or automatically.

The outermost layer of the hair follicle. It merges proximally with the inter-follicular epidermis and distally with the hair bulb.

The superior border of the permanent parietal area of hair that extends posteriorly from a line drawn vertically between the tragus and the beginning of the occipital fringe.

The entire process of harvesting a fraction of a follicular unit so that one portion of the follicular unit is harvested from the donor area while the other portion of the follicular unit remains in the donor area.

A term that describes the integrated structure of the hair follicle, hair shaft, adjoining arrector pili muscle and associated sebaceous gland.

An inactive substance prescribed as if it were an effective dose of a needed medication.

A physical or emotional change occurring after a substance is taken or administered that is not the result of any special property of the substance.

An autologous preparation of plasma with platelets that is capable of secreting growth factors and cytokines that stimulate stem cells. Some hair transplant surgeons have used PRP in hair transplantation procedures either by storing the grafts in PRP until they are placed on the scalp or by injecting PRP into the scalp prior to placement of grafts. The results of studies pertaining to the use of PRP as an adjunctive modality in hair transplantation remain controversial.

The removal of one or more terminal hairs by pulling out a follicular group with forceps and intending to remove viable follicles from the donor area that can be ed in the recipient area .

The condition of cicatricial alopecia where the scarring that occurs obliterates follicular ostia and causes the remaining ostia to coalesce so that several follicles emerge out of one site.

Refers to a group of rare, idiopathic, inflammatory scalp disorders that result in permanent hair loss. Cicatricial alopecias are traditionally classified by their inflammatory infiltrate (lymphocytic, neutrophilic, mixed). The inflammatory process affects mainly the upper portion of the follicle and is followed by a permanent destruction of the hair follicle. Primary cicatricial alopecia frequently starts on the central and parietal scalp before progressing to other sites of the scalp. A lack of follicular ostia is the hallmark of scaring alopecia. Crucial to the diagnosis if cicatricial alopecia is a detailed clinical history and one or two biopsy samples of an active lesion. The goal of any scalp reduction surgery are possible once the lesions are burnt out and stable. Graft survival may not be as good as in androgenetic alopecia and disease reactivation is possible at any time after surgery.

Potent bioactive lipid messengers. They cause many physiological responses.

A chronic asymptomatic primary cicatricial alopecia most often involving the vertex. It is non-inflammatory. The classic appearance of pseudopelade is the so-called footprints in the snow. Potent corticosteroids, hydroxy-chloroquine, and thalidomide have all been used.

A simple diagnostic test that can be performed to determine the severity and the of the hair loss. Results can vary depending upon when the hair was last shampooed and combed. Approximately 50-60 hairs are grasped between the thumb, index and middle fingers from the base of the hairs near the scalp and firmly, but not forcefully tugged. If more than 10% or 6 hairs are pulled away from the scalp, this constitutes a positive pull test, which implies active hair shedding.

The anterior traction used for the removal of the graft after it has been punched. Grafts may be pulled by a one-hand pull with single forceps, a two-hand pull with two forceps or with suction.

A surgical instrument used to obtain small samples of tissue.

Refers to the removal of hair grafts using a round punch of various sizes.

An area where hair loss has occurred and hair follicles will be implanted during a hair transplant procedure. There are many methods of creating recipient sites including lightning blades, minde blades, custom-cut razor blades, and various needles.

Refers to the influence of the recipient site scalp on the growth of transplanted hairs.

The enzyme that converts testosterone to the potent androgen dihydrotestosterone (DHT). It exists as three isozymes whose tissue distribution varies.

A term that refers to rotation followed by oscillation employed during the penetration of the punch. Rotational speed, arc of rotation, ramp (amplitude from starting position to ending position) of rotation, ramp of arc, and duration of each individual cycle may be controlled.

A procedure whereby the punch is rotated a full repetitive 360-degree cycle during the penetration of the skin. This is usually done by automatically.

The first type of graft used in hair transplantation. The round graft is obtained from the donor site by surgical removal and may be used as is or sliced into smaller sections for micro, mini or slit grafts.

Incisions made parallel to the direction of hair growth

An over-the-counter herb. It Inhibits 5-a reductase conversion of testosterone to DHT.

A procedure that is implemented when there is diagnostic uncertainty and when therapeutic options will be altered by an accurate diagnosis. Scalp conditions that usually require biopsy include all forms of scarring alopecia.

A procedure that is implemented when there is diagnostic uncertainty and when therapeutic options will be altered by an accurate diagnosis. Scalp conditions that usually require biopsy include all forms of scarring alopecia.

A medical tattoo application for balding or thinning hair.

A procedure that removes the bald scalp and brings the edges of the hair-bearing scalp closer together. Scalp reduction is now seldom performed as the primary surgical treatment for alopecia.

A type of procedure that involves the lifting and rotation of a strip of hairy scalp that is placed into an area of simultaneously removed balding skin.

A superficial cutting of the epidermis and dermis with a punch to produce a superficial circumferential or semicircle incision around a follicular grouping.

A gland located close to the ion of the arrector pili muscle. It secretes sebum to the epidermal surface.

An inflammatory condition of the skin that most commonly occurs on the scalp, face, and chest. The term dandruff or pityriasis capitis corresponds to a milder form of seborrheic dermatitis that is thought to result from a combination of factors. Clinical features can range from fine scaling of the scalp to erythematous patches. It is a relapsing condition that may require maintenance treatment. Anti-dandruff shampoos are readily available and effective in most cases. Common active ingredients include selenium sulfide, zinc pyrithione, ketoconazole, miconazole, and ciclopirox .Tar-based shampoos are also effective.

A type of hair loss that naturally occurs with age. It is described as a diffused thinning involving the entire scalp due to a steady decrease in thick terminal hairs. It is not clear whether this is distinction of androgenetic alopecia or if it is simply a continuation of it in later life.

Sentinel hairs refer to the very fine single hairs that scattered in front of the hairline to soften the appearance of the hairline .

A method by which the surgeon holds the punch and the forceps in both hands at the same time. The grafts are first cut with the punch in one hand and then removed with the forceps held in the other hand, one graft at a time and in rapid sequence.

This is when a sharp punch is ed along the course of the follicle to facilitate its extraction.

The creation of slits over the recipient area. Important considerations include slit size, depth and angle of incision and direction.

Hair obtained from a donor site directly or sectioned from a larger round graft is ed into a slit made in the scalp by the tip of a scalpel blade.

Dividing the donor strip into sections of variable widths according to the desired graft size called as slivering. The slivering technique has been compared to slicing a loaf of bread, an analogy in which the loaf is the strip and the emerging slices are the slivers. Creating the ideal sliver without transection is the most difficult step in graft preparation. The use of magnification equipment is essential for the creation of slivers

An aldosterone antagonist employed in clinical practice as a potassium-sparing diuretic. It reduces adrenal androgen production and exerts a competitive blockade on androgen receptors in target tissues. This medication has been used off-label in female pattern hair loss. Certain types of medication that bear systemic anti-androgen effects are contraindicated in men and should not be used in pregnancy due to their teratogenic effects.

The divergence of follicles from one another that typically occurs at the lower one-third of the follicular unit.

The action of separating a portion of the follicles from a group (follicular family or follicular unit) with the punch in vivo (or in situ).

Cells that reside in rather undifferentiated, quiescent states and form precursors, transient amplifying cells, that provide further proliferation and differentiation into the different cell types. Hair follicle stem cells are multi-potent, capable of proliferation and able to give rise to all cell types of the hair, the epidermis and the sebaceous gland.

Methods that relate to the steps that need to be applied (with a punch or other cutting tool), to release the graft from the surrounding tissue. All methods require a last final step common to all the techniques: the collection of the follicle with forceps or suction.

A technique for harvesting donor hair that involves the excising of a horizontal section of safe donor hair from the occipital, parietal and occasionally temporal regions. The resulting wound is sutured or stapled and leaves a linear scar.

A graft extracted from a follicular group where a portion of the follicular group remains in the donor area.

The border of hair that extends from the fronto-temporal point to a point that lies straight up from the external ear meatus.

The resting stage of the hair cycle; club hair is the final product and is eventually shed. The telogen stage typically lasts for two to three months before the scalp follicles re-enter the anagen stage and the cycle is repeated.

Refers to the excessive loss of telogen hairs due to an abnormality in hair cycling. It may occur in response to a number of triggers including fever, hemorrhage, severe illness, stress, childbirth, crash dieting and iron deficiency. It typically occurs approximately 3 months from the time of the precipitating event.

Refers to the two upper outer corners where the forehead meets the hairline. This is usually the first area where male pattern baldness is observed, causing the hairline to recede.

Large, usually pigmented hairs with a diameter of greater than 0.06 mm and a length greater than 1 cm. The hair bulb is rooted deeply in the subcutaneous fat.

A term used to describe the attachment of the connective tissue sheath and outer root sheath to the surrounding adipose of a follicle.

A condition caused by a dermatophyte infection of the hair follicle. It can be inflammatory or non-inflammatory.

A reconstructive balloon-like device that can be used to enlarge the hair-bearing scalp on the sides of the head, providing a larger supply of hair with which to replace the bald areas. It is often used in hair flap techniques and scalp reductions.

A device used to stretch the scalp. It is often used to speed up the process of scalp reduction by stretching the sides of the scalp that contain hair to achieve rapid elimination of bald areas.

Keratin-based fibers that adhere to the scalp and existing hair. They help thicken the appearance of existing hair and camouflage the balding areas on the scalp. Toppik Hair Building Fiber magnetizes the hair with static electricity and will stay in place until the following shampoo.

A condition that is caused by excessive stretching of the hair shafts through hair-styling practices. Thinning and recession involve the frontal area, but may extend into the temporal regions. Prolonged traction alopecia can scar the new hair follicle and cause permanent hair loss. Hair transplantation is successful in lowering the receded frontal hairline and re-establishing the appropriate density.

A relatively uncommon condition usually detected in early childhood. Hair loss presents itself near the frontotemporal point, in a triangular pattern, with the base of the triangle directed anteriorly. The area may be entirely hairless or have small vellus hairs scattered throughout. Triangular alopecia is amenable to hair transplantation and excellent cosmetic results can be achieved.

A type donor scalp closure. The term trichophytic (i.e., promoting hair growth) is used to describe various techniques in manipulating the donor site wound with the goal of having at least some hair grow through the scar to diminish its visibility.

A dermatoscopy of the hair and scalp. It can be performed with a handheld dermatoscope or a digital videodermatoscopy system. It may be applied in the differential diagnosis of multiple hair and scalp diseases.

This refers to the removal of the dermis and other undesired perifollicular tissues of a graft under the microscope with the aim of slimming the graft.

A simple clinical test that is used to show hair fiber fragility. With one hand, a group of hairs is held while the other hand pulls away the distal ends. Any hair breakage is considered abnormal and is a sign of hair fragility

The area used to add rigidity and to create a more stable platform for the procedure.

Small, soft hairs with a diameter less than 0.03 mm and a length less than 1 cm. They have no pigment.

The most posterior area of male pattern baldness that is characterized by a whorl arrangement of hair direction. It extends from the posterior border of the mid-scalp to the posterior curved parieto-occipital fringe of hair.

The most posterior point of the top or mid-scalp. It generally lies just behind the highest part of the skull and is the approximate point where the hair changes direction from a predominantly anterior, or radially anterior direction, to a whorl.

The circular spiral pattern that exists in the vertex.

Signaling is critical for hair follicle growth and components of this pathway are required for the induction of hair recycling. The presence of WNT agonists and antagonists is likely to lead to the appropriate balance of WNT activity in actively growing and cycling hair follicles.

Crucial to enzyme functioning. Zinc deficiency is also associated with alopecia.