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Flashcards in Hair Restoration Deck (22):
1

A 27-year-old man comes to the office for hair restoration to correct alopecia of the scalp. He sustained a burn injury to the scalp when he was a child and underwent split-thickness skin grafting to treat the burn. Micrograft hair transplantion to restore the hairline is planned. Which of the following is the most likely percentage of micrograft survival and ultimate hair growth in this patient?

A) 10%
B) 25%
C) 50%
D) 85%
E) 95%

The correct response is Option D.

Because of their small size, micrografts and minigrafts appear to have a lower metabolic requirement to thrive. They tend to grow in areas of fibrosis and burn scars and over skin grafts and flaps, including split-thickness skin grafts. The rate of survival and ultimate hair growth under these circumstances appears to be approximately 85%, compared with approximately 95% on unscarred, healthy tissue. More recently, follicular unit grafts have been used in hair transplantation.

 

2

A 41-year-old woman comes to the office for consultation regarding breast reconstruction after mastectomy. She is also embarrassed by her sudden loss of hair as a result of chemotherapy with paclitaxel. All of her hair has fallen out, and she wears a wig. Which of the following is the most likely diagnosis for this patient's hair loss?

A) Alopecia areata
B) Anagen effluvium
C) Androgenetic alopecia
D) Telogen effluvium
E) Traction alopecia

The correct response is Option B.

Anagen effluvium occurs after an insult to the hair follicle that impairs its mitotic or metabolic activity. This hair loss is commonly associated with chemotherapy. The characteristic finding in anagen effluvium is the tapered fracture of the hair shafts. The hair shaft narrows as a result of damage to the matrix. Eventually, the shaft fractures at the site of narrowing and causes the loss of hair. Hair regrowth occurs after the cessation of chemotherapy.

Androgenetic or androgenic alopecia is caused by the action of androgens. Dihydrotestosterone (DHT) is partially to blame, as it is in men. Androgenic alopecia can be caused by a variety of factors tied to the actions of hormones, including some ovarian cysts, taking high-androgen-index birth control pills, pregnancy, and menopause.

Telogen effluvium is attributable to stress on the body, such as childbirth, malnutrition, severe infection, major surgery, or extreme mental stress. Many of the 90% or so of hairs in the growing (anagen) or transitional (catagen) phases can shift all at once into the resting (telogen) phase. A few weeks to several months after the stressful event, a shedding phenomenon called telogen effluvium begins. It is possible to lose handfuls of hair at a time. This phenomenon is usually self-limited, and hair growth returns.

Alopecia areata is an inflammatory condition thought to result from the immune system attacking the hair follicles at the root. Treatment may include steroids or minoxidil. Hair loss can be temporary or permanent.

Traction alopecia is caused by localized trauma from tight hairstyles, braids, cornrows, etc. If recognized early enough, the hair will grow back.

 

3

A 35-year-old woman with diffuse hair thinning comes to the office for evaluation of hair transplantation. Physical examination shows facial hirsutism, acne, and diffusely decreased hair density over the crown and frontal scalp, except for the frontal hairline, which is quite well preserved. The scalp skin appears normal. Which of the following is the most likely underlying cause?

A ) Alopecia totalis
B ) Polycystic ovary syndrome
C ) Psoriasis
D ) Tinea capitis
E ) Trichotillomania

The correct response is Option B.

Although all options listed can cause hair loss, psoriasis and tinea capitis would be associated with visible scalp changes, such as scaling or crusting. Trichotillomania, which is traction alopecia from compulsive hair pulling, would be unlikely to show a diffuse hair loss with sparing of the frontal hairline. Alopecia totalis, by definition, is total hair loss over the entire scalp, and does not fit the patient’s description.

This woman has female pattern hair loss (FPHL), which is the preferred term for androgenetic alopecia in females. Typically there is a reduction in hair density over the crown and frontal scalp, with relative sparing and preservation of the frontal hairline, as described for this patient. Between 10 and 40% of women with FPHL have been found to be hyperandrogenic. The presence of menstrual irregularities, marked acne, or hirsutism in this patient should prompt an investigation for polycystic ovary syndrome or other underlying causes.

4

A 30-year-old man with alopecia undergoes micrografting for reconstruction of the anterior hairline. The patient should be counseled to expect which of the following hair growth timelines in grafted areas postoperatively?

A ) No growth for one month, followed by normal growth

B ) Immediate hair loss followed by new, normal growth after one month

C ) Immediate hair loss followed by new, normal growth after three months

D ) Growth for one month, followed by hair loss and then new, normal growth after three months

E ) Immediate normal growth

The correct response is Option D.

Following micrografting, the patient has hair growth for one month followed by hair loss and then normal growth after three months. Once the grafting is completed, there is an initial period of false growth lasting three to four weeks. The hair follicles then pass into the telogen phase, and this new hair growth is lost. The telogen phase lasts two to three months; following this, normal permanent growth begins at a rate of 1 cm monthly. Therefore, a total of approximately six months is required for the onset of permanent hair growth in the grafted area.

5

A 15-year-old boy is referred to the office for management of alopecia areata. Physical examination shows that more than 50% of the scalp is involved. Which of the following is the most appropriate management?

(A) Administration of finasteride

(B) Construction of a scalp rotation-advancement flap

(C) Injection of a corticosteroid

(D) Transplantation of follicular units

(E) Observation

The correct response is Option C.

Alopecia areata (AA) is a recurrent nonscarring type of hair loss that can affect any hair €‘bearing area. Clinically, AA can present with many different patterns. Although medically benign, AA can cause tremendous emotional and psychosocial stress in affected patients and their families. The pathophysiology of AA remains unknown. The most widely accepted hypothesis is that AA is a T €‘cell €“mediated autoimmune condition that is most likely to occur in genetically predisposed individuals.

 

Because AA is believed to be an autoimmune condition, corticosteroids have been used to treat this condition. Few studies are available regarding the efficacy of intralesional corticosteroids, but they are used widely in the treatment of AA. Intralesional corticosteroids are the first €‘line treatment in localized conditions. In a study including 84 patients, regrowth on treated areas was present in 92% of patients with patchy AA and 61% of patients with alopecia totalis (AT). Regrowth persisted three months after treatment in 71% of patients with patchy AA and 28% of patients with AT. Regrowth usually is seen within four to six weeks in responsive patients. Patients with rapidly progressive, extensive, or long €‘standing AA responded poorly. Another study showed regrowth in most patients (480) treated with intralesional corticosteroids, except in two patients with alopecia universalis (AU). Hair growth may persist for six to nine months after a single injection. Injections are administered intradermally using a 3 €‘cm3 syringe and a 30 €‘gauge needle. Triamcinolone acetonide (Kenalog) is used most commonly; concentrations vary from 2.5 to 10 mg/cm3. Less than 0.1 cm3 is injected per site, and injections are spread out to cover the affected areas (approximately 1 cm between injection sites). Adverse effects mostly include pain during injection and minimal transient atrophy (10%). The atrophy rarely can be severe or permanent. Injections are administered every four to six weeks.

For patients with extensive AA (>40% hair loss), little data exist on the natural evolution. The rate of spontaneous remission seems to be less than in patients with less than 40% involvement. In one review of 50 patients with extensive AA, 24% experienced spontaneous complete or nearly complete regrowth at some stage during the observation period of 3 to 3.5 years. Without therapy, the relapse rate is high in patients with severe forms of AA. Surgery does not have a role in this condition.

Finasteride (Propecia) works on alopecia secondary to male pattern baldness by affecting the 5 €‘alpha reductase enzyme.

6

A 37-year-old woman who has Fitzpatrick type I skin requests intense pulsed-light therapy for reduction of blond hairs over the upper lip. Compared with a person with darker hair, which of the following best describes the outcome of this procedure?

(A) Decreased risk for permanent scar

(B) Decreased risk for prolonged erythema

(C) Increased risk for hyperpigmentation

(D) Increased risk for malignant transformation

(E) Less effective hair reduction

The correct response is Option E.

Melanin is the target chromophore for laser and intense pulsed-light (IPL) hair reduction. Melanin pigment is responsible for skin and hair color and absorbs energy at wavelengths of 250 to 1200 nm. Thermal injury to the melanin €‘containing cells of the bulb and matrix results in destruction of the hair follicle. Patients with greater melanin content have darker hair and are more likely to have effective laser or IPL hair reduction. In very fair-haired individuals, the limited melanin content makes hair reduction less effective. At higher energy levels, fair-skinned patients can have prolonged erythema. In patients with darker pigmentation, surrounding skin can absorb energy, resulting in blistering or pigment changes.

 

7

In healthy human subjects, individual hairs develop from cells at which of the following locations?

(A) Base of the follicle

(B) Cuticle

(C) Infundibulum

(D) Outer root sheath

(E) Sebaceous gland

The correct response is Option A.

Each hair is produced through the proliferation of matrix cells at the base of the hair follicles. The progeny of these cells become displaced from below, become mature, and produce keratin.

The outermost layer of the hair is called the hair cuticle, composed of hard keratin, and is responsible for anchoring the hair in its follicle by a system of interlocking scales on its inner surface.

The infundibulum is the upper portion of the hair follicle above the sebaceous duct. It is lined by surface epithelium.

The outer root sheath covers the inner root sheath and extends upward from the matrix cells at the lower end of the hair bulb to the entrance of the sebaceous gland duct. The basal layer of the outer root sheath contains inactive pigmented amelanotic melanocytes, which can produce melanin after injury such as chemical peels or dermabrasion and migrate toward the epidermis.

Sebaceous glands produce sebum and open into the hair follicle.

 

8

Alopecia results when which of the following changes in the hair growth cycle occur?

Shortened Prolonged

(A) Anagen phase Catagen phase

(B) Anagen phase Telogen phase

(C) Catagen phase Telogen phase

(D) Telogen phase Anagen phase

(E) Telogen phase Catagen phase

The correct response is Option B.

Balding occurs when the anagen phase is shortened and the telogen phase is prolonged.

Human hair undergoes a normal cycle of growth and rest characterized by three stages: anagen, catagen, and telogen. The anagen (active) phase lasts 1000 days in men and two to five years longer in women. At any one time, 85% to 90% of hairs are in the anagen phase. The catagen (degradation) phase follows anagen and lasts several weeks. During this phase, the follicular bulb atrophies and degrades. After this, the telogen (resting) phase begins and lasts two to four months. At any given time, approximately 10% of hairs are in the telogen phase. On average, 50 to 100 telogen hairs fall out every day and are replaced with new growing hairs. Balding occurs when the anagen (active) phase is shortened and the telogen (resting) phase is prolonged.

 

9

In micrografting hair transplantation, which of the following best represents the structure of the transplanted unit?
(A) Isolated hair follicles
(B) Hair follicles with dermal elements
(C) Hair follicles with subcutaneous tissue
(D) Hair follicles with galea
(E) Hair follicles with pericranium

The correct response is Option B.

Hair in healthy scalp grows in one, two, three, or four hairs, each with their own associated neurovascular bundles, sebaceous glands, sweat glands, and piloerectile muscles surrounded by collagen. These €œphysioanatomic € units, when used as micrografts, have been shown to provide excellent results in hair transplantation.

The anatomy of an individual hair follicle includes the dermal papillae bulb, consisting of the dermal and epidermal coat. The dividing cells within the bulb form a cement column of keratinized dead cells held together with a cystine matrix to make the hair shaft.

The macroscopic hair transplantation technique of hair plugs with multiple hair follicles, intervening skin, subcutaneous tissue, epicranial and subepicranial tissue can successfully transplant hair but with an unnatural appearance.
 

10

Male-pattern alopecia is typically caused by which type of genetic pattern?
(A) Autosomal dominant
(B) Autosomal recessive
(C) Multifactorial
(D) X-linked dominant
(E) X-linked recessive
 

The correct response is Option D.

Male-pattern alopecia is a genetically triggered condition in susceptible men. It is caused by a single X-linked dominant gene. This condition occurs in 60% to 80% of Caucasian men; hair loss can begin as early as age 20 years. In men with male-pattern alopecia, a genetically determined increase in the activity of 5-alpha-reductase in the susceptible follicles has been observed. Plasma testosterone levels are normal in these patients.

Hamilton €™s system has been used to classify male-pattern alopecia based on the appearance of the anterior hairline and the hair loss at the vertex. There are seven major classifications; each is used to draw conclusions regarding the potential for further hair loss and is helpful for planning surgical management.
 

11

A 44-year-old woman comes to the office for consultation regarding loss of hair on the scalp. Which of the following findings in this patient is LEAST amenable to surgical follicular transplantation?
(A) Alopecia associated with chronic telogen effluvium
(B) Alopecia at the site of surgical scars
(C) Frontal temporal alopecia
(D) Generalized thinning of hair with discrete areas of alopecia
(E) Global diffuse thinning of hair

 

The correct response is Option A.

Female alopecia differs from male alopecia in that it requires a more in-depth history and workup because of the numerous hormonal and medical causes for hair loss in women.

Alopecia due to hormonal and medical causes, including chronic telogen effluvium (persistent increased telogen hair shedding), is usually not responsive to surgical hair restoration, and such procedures may exacerbate the alopecia.

Patients with global diffuse hair thinning may benefit from surgical restoration; however, in these patients, donor hair tends to be of poor quality.

Generalized hair thinning with discrete areas of alopecia is the most common pattern of hair loss in women and is responsive to surgical restoration. Traumatic or surgical scar alopecia may also respond to surgical restoration.

Women with frontal temporal alopecia may be treated in a similar manner as patients with male pattern hair loss.
 

12

Which of the following terms represents the primary active phase of hair growth?

(A) Anagen
(B) Anaphase
(C) Metaphase
(D) Telogen
(E) Telophase 

 

The correct response is Option A.

Normal hair growth involves two primary phases. The active phase, anagen, is the phase of hair growth. In this phase, which can last three to five years, approximately 85% of hair follicles produce hair. The resting phase, telogen, heralds the loss of the hair shaft and affects approximately 15% of hair follicles at any given time. Balding occurs when the anagen phase is shortened and the telogen phase is prolonged.

Anaphase, metaphase, and telophase are all phases in cell division and the replication of deoxyribonucleic acid. They are not specifically related to hair growth.

13

Which of the following is the most common cause of male pattern baldness?

(A) Cyclical hair loss
(B) Decreased plasma androgen level
(C) Decreased plasma testosterone level
(D) Increased plasma estrogen level
(E) Inheritance

 

The correct response is Option E.

The only cause of male pattern baldness is inheritance of an X-linked autosomal dominant gene. Male pattern baldness is also influenced by other minor genetic factors. The pattern and timing of baldness and the age of onset of hair loss are influenced primarily by all of these genetic factors. 

Cyclical hair loss is characteristic of normal hair growth. Plasma androgen, testosterone, and estrogen levels have not been shown to influence the rate or timing of baldness. However, increased levels of 5_-reductase have been an isolated finding in the hair follicles of balding patients.

14

Which of the following best characterizes male-pattern alopecia?

Q image thumb

The correct response is Option B.

Male-pattern alopecia is characterized by a decrease in the anagen, or active, phase of the hair follicle and an increase in the telogen, or resting, phase. Patients with this condition have more of their hair follicles in the resting phase, and those in the active phase produce hair growth for a shorter time. Hair follicles can also be classified as either terminal, which produce larger, pigmented fibers, or villous, which produce finer fibers that have less pigmentation and are more difficult to visualize. Terminal fibers are found typically on the adult scalp, eyebrows, axilla, and pubic region, while villous fibers are noted on the forehead, bald scalp, and along the hairline itself. In patients with male-pattern alopecia, many follicles in the scalp are transformed from terminal to villous.

Minoxidil is the recommended treatment of male-pattern alopecia. This agent halts the hair loss and increases the number of hairs as well as the diameter of the existing hairs, but is only effective in patients with mild to moderate baldness.

15

According to the donor dominance concept of hair transplantation, which of the following is the most appropriate donor site?

(A) Frontal scalp
(B) Occipital scalp
(C) Parietal scalp
(D) Sideburn
(E) Vertex

The correct response is Option B.

In order to successfully transplant hair using minigrafting or micrografting techniques, the surgeon must understand the concept of donor dominance, which states that each hair follicle possesses its own individual, genetically-defined lifespan. Because of this, hair follicles located in those areas that tend to have a longer lifespan will continue to possess the same lifespan even after they have been transplanted. The hairs of the occipital scalp have the longest genetically-defined lifespan in most patients; in addition, this donor site is acceptable aesthetically.

Depending on the classification of male-pattern alopecia, early hair loss can occur in the frontal, parietal, or vertex regions. The sideburns often have a lifespan that is genetically similar to the occipital area, but the donor site is quite small and usually unacceptable.

16

The mechanism of action of finasteride (Propecia) involves inhibition of which of the following enzymes?

(A) 2beta-hydroxylase
(B) 5alpha-reductase
(C) 6beta-hydroxylase
(D) 7alpha-hydroxylase

 

The correct response is Option B.
Finasteride is a competitive and specific inhibitor of type II 5alpha-reductase that converts testosterone into dihydroxytestosterone (DHT). Type I 5alpha-reductase is predominant in the sebaceous glands of the skin, scalp, and liver; type II 5alpha-reductase is also found within the liver, as well as in the prostate, seminal vesicles, epididymides, and hair follicles. The conversion of approximately one-third of circulating DHT is mediated by type I, and type II is responsible for the conversion of the remaining circulating DHT.

In men with androgenetic alopecia, hair follicles within the balding areas of scalp are miniaturized, and DHT levels are increased. The mechanism of action of finasteride involves preferential inhibition of the type II isozyme. Administration of finasteride rapidly decreases the concentrations of DHT within the scalp and serum, reaching a suppression percentage within the serum of 65% during the first 24 hours after oral administration of 1 mg.

The relative contributions of these decreases to the overall treatment effect of finasteride have not been defined. Finasteride appears to interrupt a key factor in the development of androgenetic alopecia in patients who are genetically predisposed to this condition.

2beta-hydroxylase converts testosterone to 2beta-hydroxytestosterone, 6beta-hydroxylase converts testosterone to 6beta-hydroxytestosterone, and 7alpha-hydroxylase converts testosterone to 7alpha-hydroxytestosterone.

 

17

A 27-year-old man has traumatic absence of the lateral third of the right eyebrow one year after sustaining avulsion and laceration injuries to the forehead and cheek. On current physical examination, there is an avulsion scar in the supraorbital region and a laceration extending from the lateral canthus directly posterior to the temporal scalp, both of which are well healed. The patient would like to undergo reconstruction of the avulsed eyebrow.

Which of the following is the most appropriate reconstructive option?

(A) Composite scalp graft containing hair follicles
(B) Median forehead flap containing hair-bearing tissue from the anterior scalp
(C) Temporal scalp flap based on the ipsilateral superficial temporal artery
(D) Washio flap
(E) Microplug hair transplantation

The correct response is Option A.


In this patient who has absence of the lateral third of the eyebrow resulting from trauma, composite grafting from the scalp is the most appropriate reconstructive option. This technique would be associated with the greatest chance for hair growth in this patient; in addition, the donor scar would be inconspicuous.

Reconstruction with a median forehead flap is a procedure that requires multiple stages and would result in an unsightly donor site scar. Both the temporal scalp flap and Washio flap would be based on the posterior temporal branch of the superficial temporal artery; however, this artery was most likely transected when the patient sustained the facial laceration, eliminating the possibility of using these flaps. Microplug hair transplantation is unreliable over scar tissue, especially traumatized soft tissue and radiated scars.

 

18

A 35-year-old man with male-pattern alopecia undergoes punch grafting for reconstruction of the anterior hairline. Which of the following best describes the pattern of hair growth seen in the grafted area postoperatively?

(A) Immediate normal growth
(B) No growth for one month followed by immediate normal growth
(C) Immediate hair loss followed by new normal growth after three months
(D) Growth for one month, followed by no growth for three months, and then resumption of new normal growth
(E) Growth for one month, followed by hair loss, and then new normal growth after three months

 

The correct response is Option E.

Following punch graft transplantation, the patient has hair growth for one month, followed by hair loss, and then new normal growth after three months. Once grafting is completed, there is an initial period of false growth lasting three to four weeks. The hair follicles then pass into the telogen phase, and this newly grown hair is shed. The telogen phase lasts two to three months; following this, normal permanent hair growth begins at a rate of 1 cm monthly. Therefore, a total of approximately six months is required for the onset of permanent hair growth in the grafted area.

 

19

Hair follicles are found in which of the following layers of the scalp?

(A) Epidermis
(B) Papillary dermis
(C) Reticular dermis
(D) Subcutaneous layer

The correct response is Option D.

The hair follicles are located within the subcutaneous layer of the scalp. Human hair is primarily composed of the keratin protein; the hair shaft is produced by the matrix, which is in turn produced by the follicle. Hair follicles are indentations of the epidermis located within the subcutaneous layer of the scalp. It is important to know the anatomy of the hair follicle in order to successfully harvest and transplant scalp hair, which can be retained with some degree of permanence following transplantation. Because successful punch grafting depends on meticulous technique, the grafts should be harvested at the appropriate depth while avoiding trauma to the hair follicles.

 

20

A 55-year-old man who has had stable hair loss for the past several years wishes to undergo hair transplantation. Conservative management with administration of finasteride has not been successful. On examination, he has Hamilton's class 6 male pattern alopecia that extends from the anterior hairline to the vertex. He has dense, curly hair in the parieto-occipital region of the scalp and excellent scalp vascularity and elasticity. 

Which of the following is the most appropriate initial management?

(A) Psychological profile and screening
(B) Trial therapy with minoxidil
(C) Establishing the anterior hairline with punch grafts
(D) Establishing the anterior hairline with scalp flaps
(E) Sagittal scalp reduction

The correct response is Option E.

Scalp reduction is currently the most appropriate management of male pattern alopecia. This technique is simple and associated with few complications. Surgical removal of the hairless scalp will diminish the total area that requires grafting and will assist with conservation of donor sites. Although various excision patterns can be used based on baldness pattern, sagittal excision patterns are preferred because they will remove the greatest amount of bald skin due to the excess of scalp laxity seen in the sagittal plane. The surgeon should perform scalp reduction before surgically re-establishing the anterior hairline.

Minoxidil is an antihypertensive drug that has been shown to increase hair growth when applied to the scalp of men who have thinning hair. However, this drug does not work in patients who have extensive hair loss, such as those 
Psychological screening is not routinely performed in patients who request treatment of male pattern alopecia.

 

21

Which of the following is most closely associated with male pattern alopecia?

(A) Absence of a genetic predisposition
(B) Decreased activity of 5alpha-reductase within genetically susceptible hair follicles
(C) Increased serum level of testosterone
(D) Prolonged anagen phase
(E) Prolonged telogen phase

 

The correct response is Option E.

Male pattern alopecia is associated with a prolonged telogen, or quiescent, phase of the hair growth cycle. During this phase, the follicle becomes inactive, and active hair growth ceases.

Inheritance is the only known cause of male pattern alopecia. Although hereditary alopecia is controlled by a single, dominant, X-linked autosomal gene, polygenetic modifying factors, such as androgen production and age, affect its expressivity. Male pattern alopecia can only be triggered by a normal adult male serum androgen level if there is genetic predisposition.

Alopecia results from increased 5alpha-reductase activity within genetically susceptible follicles. It has not been shown to be associated with increased plasma levels of testosterone. The anagen phase of the hair cycle, during which hair actively grows, is typically shortened in patients with alopecia.

 

22

Which of the following is most closely associated with the anagen phase of the hair growth cycle?

(A) Active hair growth
(B) Destruction of the follicular bulb
(C) Duration of two to three weeks
(D) Keratinization of the base of the hair
(E) Lack of hair growth

 

The correct response is Option A.

Inheritance is the only known cause of male pattern alopecia. Although hereditary alopecia is controlled by a single, dominant, X-linked autosomal gene, polygenetic modifying factors, such as androgen production and age, affect its expressivity.

The growth cycle of hair follicles is divided into three distinct phases Ð anagen, catagen, and telogen. In the anagen phase, which lasts approximately three years, the hair actively grows through division and keratinization of the follicular cells. Approximately 90% of the scalp hairs are involved in this phase. In the catagen phase, the follicular bulb is destroyed and the base of the hair is keratinized; this phase lasts approximately two to three weeks. Finally, in the telogen phase, the follicle is inactive and active hair growth ceases. Approximately 10% of the scalp hairs are in this phase at one time.