jama facial plastic surgery journal club slides: androgenetic alopecia

Copyright restrictions may apply

JAMA Facial Plastic SurgeryJournal Club Slides:

Androgenetic Alopecia

Rousso DE, Kim SW. A review of medical and surgical treatment options for androgenetic alopecia. JAMA Facial Plast Surg. Published online September 4, 2014. doi:10.1001/jamafacial.2014.316.


Introduction

• Androgenetic alopecia (AGA) is the most common form of hair loss in both men (50% affected by age 40 years) and women (32% older than 20 years affected).

• In men with AGA, hair loss begins at the bitemporal anterior scalp with progressive involvement of the vertex and mid-frontal regions. This pattern is due to androgen-sensitive hair follicles in the frontal and vertex regions, whereas the occipital and temporal scalp follicles are androgen insensitive.

• 5-Alpha reductase converts testosterone to dihydrotestosterone, which triggers the miniaturization of AGA-sensitive hair, resulting in thinning of hair and permanent loss.


Introduction

• In AGA, the ratio of hair in anagen phase to telogen phase decreases with each successive hair cycle. As a result, more hair is in telogen phase, thereby delaying the cycle back to anagen phase.

• Oral finasteride (Propecia) and topical minoxidil (Rogaine) are the only 2 clinically proven, US Food and Drug Administration–approved medical treatments for AGA in the United States.

• There are various types of hair restoration procedures, including scalp reduction, scalp expansion, scalp flaps, and hair transplantation. Currently, follicular unit transplantation is the gold standard of hair restoration surgery.


Purpose

• The article reviews the current state of medical and surgical treatment options for patients with AGA.


Relevance to Clinical Practice

Initial Evaluation

• Diagnosis of AGA in men is made through careful history and examination.

• Common features of AGA include the characteristic pattern of hair loss, family history of hair loss, and the characteristic thinning of the hair (miniaturization).


Relevance to Clinical Practice

Initial Evaluation

• In women, although AGA is common, the physician needs to consider other potential medical causes of hair loss.

• Potential medical causes for hair loss include pregnancy or hormonal changes, thyroid conditions, anemia, and use of some medications. Psychological stress or autoimmune conditions may also lead to hair loss. Once the cause has been identified, medical treatment should be directed toward correcting that medical problem.


Description of Evidence

Medical Management

• Oral finasteride (Propecia) is a selective type 2 5-alpha reductase inhibitor that reduces serum dihydrotestosterone implicated in the pathophysiology of AGA. – About two-thirds of patients using finasteride experienced increases in

total and anagen hair counts.

• Topical minoxidil (Rogaine) is an antihypertensive medication that acts on the endothelial smooth muscle cells. The exact mechanism of action on the hair follicle is unknown.– About 60% of men who used minoxidil noticed improvement in hair

count.



Hair Transplant Surgery

Basic Concept• Alopecia becomes noticeable once the hair density diminishes by 50%.

• Without creating additional hair, hair transplantation allows redistribution of hair from the area unaffected by hair loss to the area that has undergone perceptible changes.

• The occipital and temporal scalps, also known as the safe donor area, are resistant to androgen-mediated hair loss and will retain this property when transferred to other areas of the scalp.




Harvesting the Hair Graft• Natural hair exists in groupings of 1-3

individual follicles in a cluster, also known as the follicular unit. This is the physiological unit that is harvested and transferred during follicular unit hair transplantation.

• Two techniques are available for harvesting the follicular unit grafts:– Donor strip technique.– Follicular unit extraction technique.




Harvesting the Hair Graft• Donor strip technique

– Traditional method of obtaining the follicular unit grafts from the safe donor area.

– Large amount of follicular unit grafts can be harvested, and it is quicker and more cost-effective than the alternative method.

– It may leave a visible, linear scar at the donor site.




Harvesting the Hair Graft• Follicular unit extraction technique

– Newer variation of this method involves automated systems (ie, NeoGraft).

– The donor site heals more quickly than with the strip harvest technique, and there is no linear scar.

– It is more time-consuming and relatively more costly than the traditional strip harvest technique.




Hairline Design and Graft Site Creation• Goal of hairline design should be to

provide the age-appropriate look that will withstand future progression of hair loss, not to recreate the original juvenile hair line.

• During graft site creation, the stereotypic angle and the direction of the hair shaft must be consistent with the specific areas of the scalp.

• Meticulous hairline design and graft site creation are the 2 key steps in achieving a natural result.




Implantation of the Hair Graft• About 20-30 follicular unit grafts per

square centimeter is an ideal density.


Comment

Future Directions

• Current medical treatments stimulate the growth of existing hair or reduce the loss of hair follicles without growing new hair follicles.

• Researchers are developing new methods to culture and clone stem cells and induce the growth of new hair follicles in humans.


• Follicular unit hair transplantation is the gold standard for surgical management of AGA.

• Medical treatment can be used in conjunction with surgery to achieve a synergistic effect.

• Donor strip technique and follicular unit extraction technique both have advantages and disadvantages.

• Through artistic planning and meticulous execution, follicular unit hair transplantation can provide a natural hairline and the appearance of dense hair.

Conclusions


Contact Information• If you have questions, please contact the corresponding author:

– Daniel E. Rousso, MD, Rousso Facial Plastic Surgery Clinic, 2700 Hwy 280, Ste 300-W, Birmingham, AL 53233 ([email protected]).

Conflict of Interest Disclosures• None reported.

jama facial plastic surgery journal club slides: androgenetic alopecia

Documents

thinning of hair

hair transplantation

hair miniaturization

ratio of hair

common form of hair

anagen hair counts

family history of hair

successive hair cycle