Vol. 14 •Issue 12
• Page 41
Laser Hair Removal
An Introduction To an Effective Therapy
By Heather E. Endicott, NP
Accounting for more than 1.5 million appointments in 2005, the American Society of Aesthetic Plastic Surgery reports that laser hair removal is the second most requested nonsurgical cosmetic procedure today. This treatment is effective and safe and can be a profitable and rewarding practice offering for nurse practitioners in a variety of settings.
The Basics
The objective of laser hair removal is to produce permanent hair reduction without damaging surrounding tissue. Laser hair removal disrupts the stem cells in the hair follicle by delivering thermal injury to target chromophores (melanin) within the hair follicle.1 The complicating factor is that the same melanin in the hair follicle is also in the epidermis. Thus, the tissue surrounding the hair follicle must be protected during treatment to avoid thermal injury.
Physiology of Hair
Hair grows in three cycles. Active hair growth occurs in the anagen phase, when the hair "bulb" (composed of matrix cells interspersed with melanocytes) rapidly develops. Laser therapy is most effective during the anagen phase, when the hair follicle is most superficial, the melanin load is at its highest, and selective damage to the hair follicles can be achieved.2
The catagen phase is the intermediate stage. During this transitional phase, the hair follicle shrinks to about one-sixth of its normal diameter. The dermal papilla cells cease proliferating, and the bulb, including the matrical melanocytes, almost completely degrades through apoptosis.
The telogen phase is the resting phase of hair growth. During this time, the bulb is completely unpigmented.
In general, one laser treatment can produce a 20% to 30% reduction in hair, and 80% to 90% hair removal is possible after a full course.1 Five to seven treatments are required to achieve maximum hair removal. Treatments are repeated approximately every 4 to 8 weeks, depending on anatomic location. This schedule is based on the natural hair cycle. Hairs begin to fall out approximately 1 to 2 weeks after laser treatment.
The ease of laser hair removal is directly correlated with skin type and hair type.2 The ideal patient presents with skin type I or II (Caucasian, blonde or red hair, freckles, fair skin, blue eyes) and dark terminal hairs (high concentration of follicular melanin, low epidermal melanin). Skin types III and IV (darker Caucasian, Asian, Mediterranean, Hispanic) experience less hair loss with each treatment.
In patients with darker skin tones, epidermal melanin competes with follicular melanin. The epidermal and follicular melanin compete for the energy (heat) released by the laser. Thus, the energy must be delivered at a lower or "safer" level to protect the skin. This results in less energy to the hair follicle and thus less hair loss.
Selective Photothermolysis
The primary scientific principle behind laser hair removal is selective photothermolysis. By choosing an appropriate wavelength, pulse duration and fluence, thermal injury can be confined to a target chromophore (follicular melanin) within the targeted structure (hair follicle).3
Laser energy is selectively absorbed by the melanin and results in thermal damage to the hair follicle. The amount and type of melanin within the follicle determines the amount of possible follicular damage. The success of hair removal depends on the hair follicle absorbing the light energy (heat) without the laser damaging the surrounding tissue. To achieve effective photothermolysis of hair follicles with minimal damage to the surrounding tissue, an understanding of the terms listed in Table 1 is necessary.4,5
Laser Choices
Multiple types of lasers are available to remove hair (Table 2, on page 44).6 Each laser is identified by wavelength. Patient with lighter skin respond well to 755-nm to 810-nm lasers. Patients with darker skin require lasers with longer wavelengths (1064-nm) that protect the epidermis from thermal injury.
Before purchasing a laser, conduct a market analysis to identify the most likely clientele in your area.
Initial Consult
A patient's first visit should encompass the collection of a detailed medical history, including previous laser treatments, medications, allergies and a review of contraindications. These include the following: recent suntan or tanning booth use, cancer, active skin infection, herpes simplex infection (any), past use of gold therapy, disease stimulated by light, photosensitizing medication or supplements, immunosuppressive disease, endocrine disorder, bleeding disorder, hypertrophic or keloidal scarring, compromised skin, pregnancy or breastfeeding, and Accutane use within the prior 6 months. A preconsultation is necessary to rule out candidates who are unsuitable for the treatment — and to ensure that all risks and benefits are understood.
The physical history should review skin color and condition and hair color, density and diameter. It is essential to determine patient expectations so that the patient knows what outcome is actually achievable. Education is the key to successful treatment and customer satisfaction.
Sun avoidance is recommended during the treatment period. Tanned patients are at increased risk for epidermal injury because melanosome pigment disperses throughout the epidermal cells after sun exposure. Thus, the energy dispersed from the laser hits the target in the skin rather than the hair, resulting in a burn. The patient may use bleaching cream to decrease melanosome pigment in the epidermal cells and reduce the risk of epidermal injury.6
Patients must stop all plucking, waxing and electrolysis 4 weeks prior to laser treatment. If the hair follicle is removed, the laser has no target, and permanent hair reduction will not be achieved.
Laser hair removal can be uncomfortable, and the use of topical anesthetics and a cooling modality can reduce discomfort. Most patients experience some degree of perifollicular edema and erythema, which can last a few minutes to a few hours.
Before the treatment session, review the risks associated with the procedure. Folliculitis, activation of herpes simplex and, in rare cases, increased hair growth along the jaw line of women of Mediterranean or Indian descent, have been reported. The following pigmentation changes may occur: hyperpigmentation or hypopigmentation, bruising, perifollicular crusting and, in rare cases, scarring. Temporary discomfort in the treatment area may occur.
Preparation of the Patient
Instruct the patient to shave the target area the day before the treatment or to use a depilatory cream. The lasers are advanced enough to detect hair that is flush with the skin. Unshaved hair results in singed hair on the laser and the patient's skin, as well as smoke, smell and increased risk of fire.
Prescribe appropriate prophylactic antiviral agents when indicated, such as with a history of herpes simplex in the area to be treated, and start dosing the day before treatment to avoid an outbreak. Remove makeup, sunscreen and any other substances from the treatment area before laser therapy.
To minimize discomfort, apply topical anesthetic to more sensitive areas such as the upper lip, bikini area and axilla. A common choice is LMX 4%.
Patients, providers and all people present in the treatment room must wear eye protection at all times a laser is active. The eye protection must be suitable for the specific laser used.
Laser treatments last an average of 5 to 10 minutes for the facial area and 30 to 90 minutes for larger areas. Treatment time is determined by multiple factors, including laser speed and the patient's height and girth.
Cold packs applied immediately before and after treatment can reduce discomfort and swelling. Instruct patients to avoid trauma to the area, including extreme temperatures associated with hot baths, intense aerobic exercise, hot tubs and steam showers. Patients should also avoid hot tubs, rivers, oceans and other bodies of water that contain high concentrations of bacteria. Bacterial exposure after treatment can result in folliculitis.
In case of extreme follicular edema, prescribe a topical steroid to be applied to the treatment area. If follicular crusting forms, treat the patient appropriately with an emollient such as Aquaphor or an antibiotic ointment such as Polysporin.
The patient may apply makeup immediately after treatment. Mineral makeup is the most appropriate choice because it does not clog pores and is nonirritating.
Before the patient leaves the treatment facility, he or she should apply sunblock to the treated area.
Emerging Technologies
Laser treatment is a quickly evolving science. Today's lasers permit treatment of all skin types, but hair color continues to influence appropriateness for therapy. Patients who have white, blond and red hairs lack enough follicular melanin to achieve successful permanent hair removal with a laser. Scientists are now studying 5-amino-levulinic acid (ALA) photodynamic therapy (PDT), a process that is highly selective for the anagen phase and is independent of hair color. This research, led mainly by DUSA Pharmaceuticals Inc., has produced promising results thus far.7
Time and money are always concerns for patients, and two new technologies may provide good news on both fronts. The first is the use of high-speed scanners (such as that being developed by WaveLight) to increase the precision and speed of treatment. The next is home-use devices that induce temporary hair loss. This would allow patients to remove hair in the privacy of their own homes. Advances are being made in both areas, but no product is close to market approval.
Large treatment areas such as the back or chest continue to present unique issues. It's dangerous to apply large amounts of topical anesthetic agents, and some patients are unable to tolerate the discomfort in sensitive areas.
A new device, the LightSheer Duet by Lumenis, uses a breakthrough technology called pneumatically enhanced light absorption (PELA). PELA stretches the skin to boost light delivery and absorption. This allows the LightSheer Duet to treat large areas in about a quarter of the time required for existing technologies. Best of all, there is little discomfort.
Putting It Into Practice
For nurse practitioners interested in providing laser hair removal, startup costs can be wide-ranging. The average laser system costs $70,000 to $120,000 when purchased new. Options such as leasing or used equipment purchase can reduce some of the initial outlay.
The average patient charge per laser hair removal treatment ranges from about $50 to $100 for the upper lip and $300 to $800 for the legs. The average monthly revenue for laser hair removal can therefore range from $5,000 to $40,000, depending on the number of patients treated.
I have taught numerous NPs how to perform laser hair removal and integrate it into their practices. My students have ranged from dermatologists to family practice physicians to medical spa personnel.
Laser hair removal can be successfully integrated into many types of practice settings. It is a quick, effective treatment with no downtime for patients. The keys to success are a strong business plan, quality laser equipment and well-trained staff.
References
1. FDA Docket K980517. July 21, 1998. Summary of Safety and Effectiveness for the EpiLaser Normal Mode Ruby Laser. Available at: http://www.fda.gov/cdrh/pdf/k980517.pdf. Accessed June 2, 2006.
2. Personal correspondence with Richard Felten, Food and Drug Administration, April 17, 2001.
3. Anderson R, Parrish J. Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation. Science. 1983;220:524-526.
4. Goldman M, Rao J. Prospective, comparative evaluation of three laser systems used individually and in combination for axillary hair removal. Dermatol Surg. 2005;31:1671-1677.
5. Baumler W, et al. The effect of different spot sizes on the efficacy of hair removal using long pulsed diode laser. Dermatol Surg. 2002;28:118-121.
6. Dierick C. Cutaneous and Cosmetic Laser Surgery: Laser Hair Removal. Goldman M, ed. New York, N.Y.: Mosby Elsevier; 2006: 135-151.
7. Anderson R, et al. The future of hair removal technology: Have we reached the end of the development line? Skin & Aging. 2006;(1):25-27.
Heather Endicott is a family nurse practitioner at La Jolla Spa MD in La Jolla, Calif. She serves as a clinical consultant for WaveLight and Lumenis. For more information on laser hair removal, contact her at hendicott@spa-med.com.
Table 1: Glossary of Terms
Laser Wavelength: The ideal laser wavelength for successful laser hair reduction delivers energy at red or near infrared wavelengths. Optimal follicular melanin absorption occurs between 700 nm and 1100 nm. The ideal wavelength is strongly absorbed by follicular melanin but not by surrounding tissue.4
Spot Size: The spot size is defined as the width of the laser beam. The optimal spot size must be large enough to maximize laser energy to the depth of the hair follicle. Spot sizes less than 7 mm deliver less than optimal energy deep into the follicle; thus, ideal spot sizes are 10 mm or greater.5
Pulse Duration: The pulse duration or pulse width is the amount of time required to deliver the energy. The pulse duration must be less than the thermal relaxation time of the target. If the pulse duration is more than the thermal relaxation time, the surrounding tissue can result in thermal damage. Thus, the longer the pulse duration, the safer the fluence (energy) delivered into the skin. Pulse widths vary from 10 milliseconds to 100 milliseconds.
Fluence: The amount of energy delivered to the skin is measured in Joules per centimeter squared (J/cm2).
Cooling: To minimize epidermal injury, epidermal cooling is necessary. The cooling agent protects epidermal melanin while delivering effective fluence to the follicular melanin. This is particularly important to darker-skinned people, who have higher amounts of epidermal melanin. Cooling modalities available for laser hair removal include the following: passive cooling with an aqueous gel or ice; active contact cooling with water encased in a glass, quartz or sapphire tip; active cooling with concurrent forced air; and active cooling with cryogen spray.
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