Baldness

Question 1

Describe embryology of hair

Answer 1

Ectoderm -> hair shaft and pilosebaceous follicle

Medoserm - deral papillae

Question 2

Describe the anatomy of hair

Answer 2

Hair shaft and root

• SHAFT: 3 layers of keratinized cells
• ROOT: = follicle = contains matrix (rapidly proliferating cells) and zone of keritinization (production of shaft)

Question 3

Describe hair growth

Answer 3

3 phases:ACT

1. ANAGEN - Proliferative phase (2-5yrs)
   
   1. 90% of follicles, longer phase in W
2. CATAGEN - Degradation phase (2-3wks)
   
   1. 2% of follicles, bulb atrophies and separates from papilla ->club
3. TELOGEN - Resting phase (3mths)
   
   1. 8% of follicles, hair sheds as attachment to papila weakens

Question 4

Describe types of hair

Answer 4

1. Lanugo - fetal hair, unpigmented, shed prior to birth
2. Vellus - infant hair, hypopigmented, replaces lanugo hair in post-natal period
3. Terminal - coarse thick hair, pigmented. May be replaced by vellus hair if follicle abnormal

Question 5

DDX of alopecia

Answer 5

CONGENITAL

• Cutis aplasia
• Ectodermal dysplasia

ACQUIRED

• Androgenic Alopecia
• Alopecia Areata (autoimmune)
• Discoid Lupus erythematous
• Lichen planopilaris
• Endocrine (hypothyroid, low iron, menopause)
• cicatricial
• traumatic
• Meds (chemo, steroids)

Question 6

Define Androgenic Alopecia

Answer 6

Gradual conversion of terminal hair to villus hair,

Question 7

What factors contribute to androgenic alopecia

Answer 7

• Genetics: inheritance of AD sex-linked gene
• Androgen sensitivity: high alpha 5 reductase activity converting testosterone into DHT
• Age: anagen phase shortend with each cycle

Question 8

How do you classify Male Pattern Baldness

Answer 8

NORWOOD

Type 1 - no frontotemporal recsession

Type 2 - frontotemporla recession posteriorly but not >2cm anterior to coronal plane by EAC

Type 3 - frnototemporal recsession posteriorly and <2cm anterior to coronal plane by EAC

Type 3 (vertex) - hair loss at vertex

TYpe 4 - both frontotemporal and vertex hair lone iwth wide band of hair separating two areas of hair loss

Type 5 - narrower band of hair compared to type 4

Type 6 - interconnected tow areas of baldness

Type 7 - sparse hair on sides/back

Question 9

How do you classify female pattern badness

Answer 9

Ludwig

Defined by vertex hair

1- mild diffuse loss

2- moderate

3- severe

Question 10

WHat are management options for baldness

Answer 10

Non-operative

• Camouflage
• Medications

Operative

• Hair transplantation
• Alopecia reduction with scalp excision

Question 11

What is Minoxedil and how is it used

Answer 11

Minoxedil = Rogaine, 2-3% applied BID, topical

MAC: possible direct stimulation of hair follcile, vasodilation (noted to cause hypertrichosis in treatment of HTN

Indications: vellus hair, not complete alopecia, <40

ADverse effect: dermatitis

Conrtaindications: CVD

Question 12

What is finasteride and how is it used

Answer 12

5 alpha reductase inhibitor, 1mg po daily

MAC- reduces conversion of testosterone to DHT, reverses hair miniturization (covnersion of terminal to vellus)

6-12mths to note effect, best in young men

ADverse: decreases libido, rapidly progresses baldness if stopped

Teratogen****

Question 13

Describe the indications for hair transplantation

Answer 13

primary alopecia

traumatic alopecia

reconstruction of eyebrows

Question 14

What is the ideal hairline

Answer 14

8-9cm from the horizontla line drawn at the suprabrow

Question 15

What are the graft types for hair transplantation

Answer 15

• Micrograft: 1-2 hairs
• Minigraft: 3-8 hairs
• Follicular unit graft: contains 3-4terminal hairs, a sebaceous gland, arrector pilli
• round graft

Question 16

Describe the steps of Follicular Unit Transplantation (traditional technique)

Answer 16

1. Pre-op: chlrohex prep, donor hair trimmed, new hairline marked 8-9cm above suprabrow
2. Analgesia: LA and sedative
3. Donor site: Occipital area + superiorly to parietal zone and anteriorly up to tragal perpendicular
4. Graft harvest
   
   1. Strip technique: 8mmx18cm = 1000-2000FU with tricophytic techqnieue (angled blade)
5. Graft preparation
   
   1. Cut into mm segments
   2. Subdivide into micro or minigrafts
6. Recipient - infiltrte tumescence
7. Transplant -
   
   1. 20-30FU per cm2= 40-60 hairs/cm2
   2. may repeat in 4-6mths
8. Post-op
   
   1. minoxidil 2-3% BID
   2. hair enters telogen phase for 3mths then anagen for new growth at 4mth

Question 17

Describe diffrence between follicular unit transplantation and follicular unit Extraction

Answer 17

Graft harvested is not as strip but as FU with small punch excisions

Disadv: can have moth eaten look as punch trasnsects

largeer donor area required

Adv: donor heals by 2’ intention w less scarring

Question 18

Complications of hair transplantation

Answer 18

Inclusion cysts, ingrown hair

Poor scarring

elevated/depressed grafts

abnormal hairline

telogen effluvium (expectoration of degradated hair)

Question 19

Describe techqnieu for alopecia reduction with excision of scalp

Answer 19

• Tissue expansion intraop with excision
• Scalp extension with silinone elastomer and anchor hooks
• Flaps :
  
  • Juri temoporoparieto-occipital
  • Elliott scalp flap (lateral flap)