Hair Transplantation Flashcards
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
D ) Growth for one month, followed by hair loss and then new, normal growth after three months
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.
Expected hair growth after micrografting
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.
Total amount of time for onset of permanent hair growth after grafting
6 months
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
(C) Injection of a corticosteroid
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 inaffected 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.
Alopecia Areata
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.
Pathophysiology of Alopecia areata
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
Treatment of alopecia aerata
Because AA is believed to be an autoimmune condition, corticosteroids have been used to treat this condition
Injections are administered intradermally using a 3‑cm3syringe and a 30‑gauge needle. Triamcinolone acetonide (Kenalog) is used most commonly; concentrations vary from 2.5 to 10 mg/cm3.
Administer ever 4-6 weeks.
Finasteride
Finasteride (Propecia) works on alopecia secondary to male pattern baldness by affecting the 5‑alpha reductase enzyme.
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 hyper pigmentation
(D) Increased risk for malignant transformation
(E) Less effective hair reduction
(E) Less effective hair reduction
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.
In very fair-haired individuals, the limited melanin content makes hair reduction less effective.
Target wavelength of melanin
250 to 1200 mm
Target chromophore for laser and IPL hair reduction
Melanin
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
(A) Base of the follicle
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.
What cells produce hairs?
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.
Hair cuticle
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.
Infundibulum (hair)
The infundibulum is the upper portion of the hair follicle above the sebaceous duct. It is lined by surface epithelium
Outer root sheath
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 inactivepigmented amelanotic melanocytes, which can produce melanin after injury such as chemical peels or dermabrasion and migrate toward the epidermis
Sebaceous glands and the hair follicle
Sebaceous glands produce sebum and open into the hair follicle.
Alopecia results when which of the following changes in the hair growth cycle occur?
Shortened vs Prolonged
(A) Anagen phase vs Catagen phase (B) Anagen phase vs Telogen phase (C) Catagen phase vs Telogen phase (D) Telogen phase vs Anagen phase (E) Telogen phase vs Catagen phase
(B) Anagen phase vs Telogen phase
Balding occurs when the anagen phase is shortened and the telogen phase is prolonged.
Balding occurs with what phase changes?
Balding occurs when the anagen phase is shortened and the telogen phase is prolonged.
Anagen phase for hair growth
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.
Catagen phase of hair growth
The catagen (degradation) phase follows anagen and lasts several weeks. During this phase, the follicular bulb atrophies and degrades.
Telogen phase of hair growth
The telogen (resting) phase begins and lasts two to four months.
At any given time, ____% of hair is in the telogen phase
At any given time, approximately 10-15% of hairs are in the telogen phase.
On average, ________ hairs fall out every day and are replaced with new growing hairs.
On average, 50 to 100 telogen hairs fall out every day and are replaced with new growing hairs.
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
(B) Hair follicles with dermal elements
Hair in healthy scalp grows in one, two, three, or four hairs, each with theirown associated neurovascular bundles, sebaceous glands, sweat glands, and piloerectile muscles surrounded by collagen. These “physioanatomic” units, when used as micrografts, have been shown to provide excellent results in hair transplantation
Physioanatomic units of hair
Hair in healthy scalp grows in one, two, three, or four hairs, each with theirown associated neurovascular bundles, sebaceous glands, sweat glands, and piloerectile muscles surrounded by collagen. These “physioanatomic” units, when used as micrografts, have been shown to provide excellent results in hair transplantation
Anatomy of an individual hair
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:
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.
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
(D) X-linked dominant
Male-pattern baldness is caused by what type of gene?
X-linked dominant
Etiology of male pattern baldness
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.
Epidemiology of male pattern baldness
This condition occurs in 60% to 80% of Caucasian men; hair loss can begin as early as age 20 years.
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
(A) Alopecia associated with chronic telogen effluvium
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.
Chronic telogen effluvium
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
Most common pattern of hair loss in women
Generalized hair thinning with discrete areas of alopecia is the most common pattern of hair loss in women and is responsive to surgical restoration.