Glossary

Acne Keloidalis
Firm, red brown papules (small bumps) and plaques on the back of the scalp at the nape of the neck of unknown etiology. It has a genetic predisposition and occurs more commonly in persons of African descent. It is treated with local injections of corticosteroids, antibiotics, and surgery. Because these lesions occur in the donor area, its presence is a relative contraindication for hair restoration surgery.

Alopecia
The medical term for hair loss of any type. It can result from illness, functional disorder, or a hereditary predisposition.

Alopecia Areata
An autoimmune condition where the body produces antibodies against its own hair follicles. It is characterized by the sudden appearance of smooth circular patches of bald spots on the scalp, beard, eyelashes, or other parts of the body. Hair transplantation is generally not indicated for this condition and treatment consists of injections with cortisone or other medical therapies. Generally the earlier the onset and the more extensive the hair loss, the worse the prognosis. Other characteristic features include: 1) exclamation point hairs – hairs tapered at the bottom due to the inflammation which causes injury to the hair shaft, 2) hair pigment changes, 3) grid-like nail pitting, 4) positive hair pull test – showing telogen hairs and hairs with tapered broken ends (dystrophic anagen hairs).

Alopecia Marginalis
Hair loss primarily at the hairline and temples which is usually caused by continued traction from braids or hair extensions. If condition persists over a length of time, hair loss may become permanent even when braiding is discontinued. Other causes of hair loss in men occurring in this distribution include a hereditary thinning in the area (unrelated to trauma) and follicular degeneration syndrome.

Alopecia Totalis
A type of alopecia areata that results in the total loss of hair on the scalp.

Alopecia Universalis
A type of alopeica areata that involves all the hair on the body including the eyelashes, eyebrows, and hair on the trunk and extremities.

Anagen
The growing phase of the hair follicle. It generally lasts from 2 to 5 years.

Anagen Effluvium
Extensive hair shedding that results from damage to the hair follicles. It appears soon after exposure to the offending agent. One can see broken hair shafts and tapered, irregular hair roots. Anagen effluvium is seen with chemotherapy and radiation therapy.

Androgenetic Alopecia
Hair loss resulting from a genetic predisposition of follicles to the affects of DHT. It is characterized the replacement of thick terminal hairs with fine, miniaturized hairs that are eventually lost. Also termed female pattern baldness, male pattern baldness, hereditary alopecia and simply common baldness.

Catagen
The intermittent stage between the growing (anagen) and resting (telogen) phases of the hair growth cycle. In this transitional phase, the follicle stops producing hair and the base of the hair follicle begins to move upwards through the dermis. This phase typically lasts 2-4 weeks.

Chronic Telogen Effluvium (CTE)
CTE is marked by increased shedding of telogen hairs and diffuse thinning especially at the temples. It affects women age 30-60 and can start abruptly with, or without, an initiating factor. It usually does not lead to complete baldness and can resolve in 6 months to 6 years. It typically has a long, fluctuating course with patients losing up to 50-400 hairs/day. Patients with CTE complain of excessive hair shedding whereas those with androgenetic alopecia complain of gradual thinning. The mechanism of CTE is felt to be a shorted anagen (growth) cycle. Unlike androgenetic alopecia, chronic telogen effluvium is not characterized by miniaturized hair follicles. Hair transplants are not indicated in CTE as the hair loss tends to be diffuse and patients should get better over time without treatment.

Density
The number of hairs in a specific area. The average hair density on the scalp is 2.25 hairs/cm².

Densitometry
Densitometry is a technique to help evaluate a patient’s candidacy for hair transplantation and predict future hair loss. It analyzes the scalp under high-power magnification to give information on hair density, follicular unit composition and degree of miniaturization.

Diffuse Patterned Alopecia (DPA)
Diffuse Patterned Alopecia (DPA) is a type of androgenetic hair loss characterized by diffuse thinning in the front, top, and vertex of the scalp. It is usually associated with a stable permanent zone.

Diffuse Unpatterned Alopecia (DUPA)
A type of androgenetic hair loss that occurs over the entire scalp so that there is no permanent zone of hair normally present in the back and sides of the scalp. The progression of hair loss is often rapid and can result in an almost transparent look due to the low density. Diagnosing DUPA is imperative, as most patients with diffuse unpatterned alopecia should not have a surgical hair restoration, as the transplanted hair will not be permanent. DUPA is a pattern more commonly seen in women. The use of densitometry is very helpful in diagnosing this condition.

Dihydrotestosterone (DHT)
DHT is a male hormone that is suggested to be the main cause for the miniaturization of the hair follicle and for hair loss. DHT is formed when the male hormone testosterone interacts with the enzyme 5-alpha reductase.

Discoid Lupus Erythematosus (DLE)
An auto-immune disease characterized by scaly red plaques with telangiectasia (fine blood vessels), plugged follicles, atrophy (thinning of the skin) and pigmentary changes. DLE often leads to local areas of scarring and permanent localized hair loss.

Treatment includes topical corticosteroids, intra-lesional corticosteroids, systemic corticosteroids, anti-malarials, topical tacrolimus topical tazarotene, topical imiquimod, isotretinoin and thalidomide. Surgical hair restoration is generally not indicated in DLE since the disease process had the propensity to recur. DLE may or may not be associated with the more generalized disease SLE.

Female Pattern Alopecia
Female pattern hair loss is characterized by a gradual thinning of the front and/or top of the scalp with relative preservation of the frontal hairline. Although the areas on the top of the scalp are affected the most, the process tends to be diffuse involving the entire scalp to some degree. In female alopecia, the genetics seem to be more complicated than a simple response to androgens. Women with female alopecia are candidates for hair transplantation only if the back and sides of the scalp are stable.

Follicular Degeneration Syndrome
A form of scarring alopecia caused by the premature shedding of the inner root sheath of the hair follicle. It eventually results in complete follicular destruction. Because it occurs in a band around the frontal part of the scalp it had been felt that the condition was due to traction. It is now felt that the condition is idiopathic and unrelated to mechanical trauma or that it can be caused by a hot comb.

Folliculitis Decalvans
A form of scarring alopecia characterized by redness, swelling and pustules around the hair follicle, leading to the destruction of the follicle and consequent permanent hair loss. Folliculitis decalvans affects both men and women and may start first during adolescence or at any time in adult life. The exact cause is unknown. In most cases Staph aureus can be isolated from the pustules but the role of the bacteria is not clear.

Treatment includes: oral antibiotics – cephalosporin, minocycline, rifampin, or intralesional corticosteroids

Frontal Fibrosing Alopecia
More common in post-menopausal women, the front part of the scalp appears shiny, smooth and devoid of hair follicles. This pattern can mimic androgenetic alopecia but, on close inspection one notes scarring and the absence of hair follicle openings.

There may be signs of inflammation including redness and scaling. The condition may be a variant of Lichen Planopilaris.

Lichen Planopilaris (LPP)
A condition affecting the hair follicles in localized scaly red patches that result in scarring and hair loss in the affected areas. The disease is characterized by a band-like layer of inflammatory cells at the upper most layer of the dermis that damages the hair follicles.

Treatment includes: potent topical corticosteroids, intra-lesional corticosteroids, systemic corticosteroids, oral retinoids, anti-malarials, and oral cyclosporine

Loose Anagen Hair Syndrome
This is a very rare condition but seen more often in females than males, presenting early in childhood, usually between the ages of 2 and 9 as diffuse patches of hair loss. This syndrome is characterized by a defective inner root sheath (abnormal keratinization) that prevents it from grasping the hair shaft cuticle. As a result the newly growing hair shaft falls out. The hair is usually blonde, feels matted or sticky, lusterless and does not require cutting. A hair-pull test is positive for anagen hairs. No systemic abnormality is associated with it. With adolescence the hair grows longer, denser and darker, but the hair pull remains positive.

Ludwig Classification
Classification of female pattern hair loss. It encompasses three stages: Mild (type 1), Moderate (type II) and Extensive (type III). In all three stages, there is loss on the front and top of the scalp with preservation of the frontal hairline. If the person’s donor hair is stable at the back and sides of the scalp, women of all three types of Ludwig Classification may be candidates for hair transplantation.

Male Pattern Baldness (MPD)
Also known as androgenetic alopecia or common baldness. This is the most common type of hair loss, caused by the affects of DHT on susceptible hair follicles. It mainly affects the frontal, top and crown of the scalp and can result in a pronounced horseshoe pattern.

Marginal Hair Loss (see Alopecia Marginalis)

Norwood Classification
Published by Dr. O’tar Norwood in 1975, this is the most common classification for describing genetic hair loss in men. The regular Norwood pattern has seven stages that begin with recession at the temples and thinning in the crown. The Norwood Class A pattern has five stages and is characterized by a predominantly front to back progression of hair loss.

Pseudo Palade of Braque
A non-specific scarring alopecia of unknown cause. It also may represent the end stage of other inflammatory scalp conditions. It presents with white or flesh-colored atrophic plaques, without active inflammation.

Systemic Lupus Erythematosis (SLE)
An auto-immune disease where the immune system attacks the body’s own cells, resulting in inflammation and tissue destruction. SLE can affect any part of the body, but most commonly affects the skin, joints, kidneys, heart and blood vessels. The course of the disease is unpredictable, with periods of flares and remissions. Lupus can occur at any age and is more common in women. The skin manifestations are quite varied and can present with localized lesions (DLE), diffuse hair loss and sensitivity to the sun. The name comes from the fact that the photo-sensitive rash that occurs on the face resembles that of a wolf.

Telogen
The resting phase (2-4 months). In this period a new hair begins to grow and the old hair is gradually forced out of the follicle and shed.

Telogen Effluvium
This condition has its onset 2-3 months after stress or insult to the scalp. Generally 35-50% of hair is affected. One can see over 300 hairs shed per day. The hairs are characteristically “club” hairs, i.e. telogen hairs that have a small bulb at the end. Telogen effluvium is much more common in women than men.

Tinea Capitis
A fungal infection of the hair follicles of the scalp characterized by the formation of small crusts at the base of the follicles. It is also referred to as ringworm of the scalp. It can result in small patches of permanent hair loss. It can be diagnosed by a scalp scraping and a hair pull tested for fungus on a KOH prep and a fungal culture. The most common organism producing this condition is Tinea Tonsurans.

Triangular Alopecia
A triangular shaped area devoid of hair that most commonly occurs in the temples. The apex of the triangle often points towards the vertex of the scalp. It can be unilateral or bilateral. Fine, vellus hairs can be seen in the bald patch. The condition appears at birth or in early childhood and is stable. The early, stable appearance, fine vellus hair and characteristic location, help to differentiate it from alopecia areata. Hair transplantation is the treatment of choice.

Traction Alopecia
Develops from continuous traction or pulling on the hair. The hair loss is most prominent at the frontal hairline and temples. It can be seen with hair systems and corn-row hair styles. It is common in African-Americans that braid or corn-row their hair. When long-standing, the hair loss can be permanent

Trichotillomania
A compulsive disorder characterized by pulling of one’s hair. The most common area is scalp hair causing patchy areas of hair loss with broken hairs of varying lengths. Most commonly seen in females ages 6 to 30. This condition can also involve the eyebrows or upper eyelashes (upper lashes are easier to grab). The diagnosis can be made by cutting or shaving the hair so that it is too short to grab and then observing the growth. Patients suspected of having trichotillomania should be sent for a psychiatric evaluation. A hair transplant is not indicated.