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    R. Rox Anderson, M.D.

Associate Professor of Dermatology, Harvard Medical School

Director of Research at the Wellman Laboratories for Photomedicine


The most efficient laser in the world, is the 800 nm semiconductor diode laser. Extremely high-power diode lasers have not been available for dermatology until now. The LightSheer(TM) Diode Laser System uses state-of-the-art diode laser arrays to achieve power, efficiency, and reliability in a small package designed for versatile office use. This paper summarizes clinical efficacy and safety data for hair removal.


Unwanted, pigmented hair is a common cosmetic problem for both sexes. Until recently, the only long-lasting method of hair removal was electrolysis, which requires tedious insertion of an electrode into each hair follicle. The late Leon Goldman first described ruby laser injury to pigmented hair follicles. Over 20 years ago, Ohshiro noted hair loss from nevi after treatment with a ruby laser. At fluences affecting hair follicles however, the epidermis was severely damaged. A detailed understanding of "selective photothermolysis" (1) later emerged, and is widely applied for vascular, pigmented lesions, tattoos, and now hair removal.

The first quantitative, controlled clinical study of laser hair removal in normal human skin was reported by Grossman, et al (2). Ruby laser pulses were delivered through a cold sapphire handpiece held in contact to protect the epidermis. This pilot study showed two significant responses of dark, terminal (coarse) hair follicles, reported by the investigators in two peer-reviewed journals:

  • Temporary hair removal for 1-3 months in all subjects, at all fluences (2).

  • Permanent reduction* of hair at fluences >30 J/cm2, for at least two years after a single treatment (3). Hair loss was greater in sites that were shaved (vs. wax-epilated) before treatment. "Permanent" is defined as significant and stable loss of hair for a period longer than the complete natural hair growth cycle (about one year).

*FDA clearance for claim of permanent reduction pending (Palomar EpiLaser).

Through a cooperative license and research agreement with Massachusetts General Hospital, Palomar supported basic and clinical research by R. Anderson and colleagues, leading to FDA clearance of the first ruby laser system for hair removal, the EpiLaser. A confusing array of devices now exists for hair removal, along with speculations about actual performance. In partnership with Coherent, Palomar continues its leadership with the introduction of revolutionary technology in a versatile laser system for dermatology, the LightSheer Diode Laser System.

Effective laser hair removal requires damage to parts of the living hair follicle responsible for production and regeneration of a hair shaft. Anatomically, there are two main target structures:

  • the "bulge," a region of epithelial stem cells located 1-1.5 mm below the skin surface

  • the "bulb," a deep, heavily-pigmented, proliferating part of anagen follicles.

The bulge is usually devoid of melanin, but is in close proximity to the pigmented hair shaft. Plucking or wax-epilation of hair shafts prior to laser treatment significantly reduces effectiveness for long-term hair loss, but does not affect temporary hair loss (2).

All hairs go through a cycle of active growth (anagen), transition (catagen), and resting (telogen) phases. The length of hair at different body sites is governed by the duration of anagen. Duration of telogen also varies with body site, and may be as long as a year on the leg. Temporary loss of hair can therefore be achieved simply by inducing telogen. This is the mechanism for the reliable, nearly complete loss of pigmented hair for several months after each treatment with the LightSheer diode system and several other lasers. It is important to realize, however, that temporary hair loss does not predict permanent hair loss-which is what most patients seek. Reliable, controlled, quantitative, long-term clinical results are the only way to be sure of performance.

The LightSheer diode laser and its unique handpiece are specifically optimized for treating pigmented hairs. This was accomplished by a combination of wavelength, high power, laser pulse duration, large spot size, convergent beam optics, aggressive skin cooling and capability for compression of the skin during delivery of each laser pulse.

There are 3 distinct responses, which account for an apparently permanent (3) reduction of pigmented, coarse hair:

  • miniaturization of hair follicles (dominant mechanism for LightSheer)

  • decreased pigmentation of regrowing hair

  • degeneration of hair follicles with replacement by fibrosis

Clinical Studies

Studies were performed at Massachusetts General Hospital and the Laser and Skin Cancer Center of New York. Large test sites on the back or thighs of 58 consecutive patients with skin type

I-V (fair to dark-skinned) and any hair color, were shaved and treated with a range of 15-40 J/cm2 fluence, using the LightSheer diode laser. Baseline and subsequent regrowing terminal hair counts were taken from high-quality digital images of each site. Adjacent, untreated control sites were also counted. Results from one and two treatments given approximately two months apart, were compared in each patient, at each fluence. Treatment at any body site elected by the patient was also given. Efficacy is best appreciated as the percentage of terminal hair which regrows over time, shown below for different fluences:

Long term hair reduction 1 year after
 treatment at 40 J/cm2 fluence, 20 ms
 pulse duration, on a male's back.

Before treatment 20 weeks after third treatment


The data in the graph above is not just "best cases", it is from all, consecutive patients treated under identical conditions. The study showed:

  • 100% of patients have complete or nearly complete, temporary hair loss for 1-3 months after each treatment, at all laser fluences.

  • Long-term reduction of hair occurred in the majority of patients.

  • Histology (not shown) was consistent with miniaturization of hair follicles, and granulo matous degeneration of hair follicles as the dominant mechanisms for loss of terminal hair.

About 70% of patients with black, brown, auburn, or red hair had long-term hair reduction, whereas only about 10% of patients with blonde hair had long-term hair reduction. The degree of long-term hair reduction was fluence-dependent.


No scarring has been observed, but might occur rarely after any skin treatment. The most common side effect, seen in about one patient in six, is transient hyper- or hypo-pigmentation, which clears in 1-6 months. Pigmented lesions such as lentigines and freckles may become permanently removed. These pigmentary changes are fluence and skin type dependent; the ideal patient for laser hair removal has dark hair and fair skin. Moderate pain, perifollicular erythema and edema occur commonly and resolve within a few days after each treatment. Local blisters rarely may occur at high fluences in dark-skinned patients.

Treatment Guidelines-Hair Removal

Skin color:

Tolerated fluence is set by epidermal pigmentation. Fair-skinned patients are most easily treated. For patients presenting with a "tan" or with dark skin type, pretreatment with topical 4% hydroquinone (or other bleaching agents), sunscreen and sun avoidance for 6 weeks, should be considered prior to laser treatment.

Hair color:

Temporary (1-3 month) hair loss almost always occurs after each laser treatment, regardless of hair color. However, the effectiveness for a permanent hair reduction is strongly correlated with hair color. Blonde or white-haired patients are unlikely to experience a permanent reduction in hair. Hair loss in these patients can be maintained if desired, by treatment at approximately 3-month intervals.


LightSheer's cold handpiece greatly reduces pain during treatment. Although less-sensitive areas (back, legs, axillae) can frequently be treated without any anesthesia, topical anesthesia is generally used, e.g. tetracaine.


Patients should not epilate or pluck hair for several weeks before treatment. Hair is shaved, usually before application of anesthetic, prior to laser treatment. After removal of anesthetic cream (if used), laser pulses at the desired fluence and spot size are delivered with the handpiece pressed firmly against the skin. The handpiece is then picked up and placed firmly on an adjacent site, until the desired area is covered. Because of active cooling, overlapping pulses to one skin site are not harmful.

Immediate responses:

The ideal immediate response for hair removal, is vaporization of the hair shaft with no other apparent effect. After a few minutes, there is perifollicular erythema and edema. If there is confluent edema or a positive Nikolski sign (epidermal separation forced by lateral pressure on the skin), fluence should be reduced.

Body site:

All body sites except the eye can be treated safely.


This high-energy laser system is specifically designed for deep tissue penetration, and strong absorption by melanin. It is capable of causing severe retinal injury when applied near the surface of an eye. Proper eye protection must also be worn by patient and operating personnel to prevent inadvertent exposure to the eyes.


The LightSheer Diode has been shown to be safe and effective for pigmented hair removal. The actively cooled handpiece combined with long pulse duration and smooth pulse structure, reduces epidermal injury.

References Cited

  • Anderson RR, Parrish JA "Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation" Science 220: 524-527, 1983

  • Grossman MC, Dierickx CC, Farinelli WA, Flotte TJ, Anderson RR "Damage to hair follicles by normal-mode ruby laser pulses" J Amer. Acad. Dermatol 35: 889-894, 1996

  • Dierickx CC, Anderson RR "Permanent hair removal by normal-mode ruby laser" Arch Dermatol. 1998 (in press)

  • Anderson RR, Parrish JA "Optics of human skin" J. Invest. Dermatol. 77:13-19, 1981

  Dermatol Surg. 2001 Nov;27(11):925-9; discussion 929-30.

Laser hair removal with alexandrite versus diode laser using four treatment sessions: 1-year results.

Eremia S, Li C, Newman N.

Division of Dermatology, UCLA, Los Angeles, California, USA.

BACKGROUND: Laser hair removal is the treatment of choice for hypertrichosis. The two most commonly used hair removal lasers are compared.
OBJECTIVE: To present the results of a comparative study examining the role of wavelength, fluence, spot size, pulse width, and cooling systems on long-term results after a series of four laser hair removal treatments using the 755 nm alexandrite and 800-810 nm diode lasers.
METHODS: The axillae of 15 untanned, type I-V patients were treated side by side four times at 4- to 6-week intervals with a 755 nm, 3-msec pulse width, cryogen spray-equipped alexandrite laser and an 800 nm, variable pulse width, cooled sapphire window-equipped diode laser. Each patient was pretested and treated with the maximum fluence tolerated at the largest spot size available for each laser (12 mm round/113 mm2 for the alexandrite and 9 mm for the diode).
RESULTS: Evaluations were done at 3, 6, 9, and 12 months after the last treatment. Twelve-month results with the alexandrite and diode lasers achieved 85% versus 84% hair reduction. The fact that tan avoidance was strictly followed permitted the use of relatively high fluences (25-30+ J/cm(2)) even in type IV patients. For most patients, four treatment sessions using high fluences (30-40 J/cm(2)) with relatively large spot sizes (12 mm round for the 755 nm alexandrite and 9 mm for the 800 nm diode) resulted in 12-month hair reductions in the 90% range.
CONCLUSION: Both the alexandrite and diode lasers in this 12-month study produced excellent long-term hair reductions.

PMID: 11737125

Dermatologic Surgery
Volume 27 Issue 11 Page 950 - November 2001

An In Vivo Study Comparing the Efficacy and Complications of Diode Laser and Long-Pulsed Nd:YAG Laser in Hair Removal in Chinese Patients

Henry H. Chan, FRCP* Shun-Yuen Ying, FRCS Wai-Sun Ho, FRCS David S. Y. Wong, FRCS and Lai-Kun Lam, FRCS
Background: Lasers with long wavelengths are less well absorbed by melanin and are considered to be particularly suitable for hair removal in dark-skinned patients.
Objective: To compare the efficacy and complications of 800 nm diode and long-pulsed 1064 nm Nd:YAG lasers in laser-assisted hair removal in Chinese patients.
Methods: Fifteen women had hair removal treatments (13 axillae and 2 legs) with diode laser on one side and Nd:YAG laser on the other. They were followed up for 36 weeks. Subjective assessments included the degree of immediate pain and the degree of hair regrowth. Clinical photographs were taken for evaluation by two independent observers to assess complications and the degree of hair regrowth.

Results: Long-pulsed Nd:YAG laser was found to be significantly associated with a greater degree of immediate pain after laser surgery (P = .0001, independent sample t-test) and also had a longer laser time (P = .0001, independent sample t-test). Besides transit adverse effects such as erythema and perifollicular edema, only one patient developed hypopigmentation at week 6 which resolved by week 36. Although regrowth rates were low at week 6 (subjective rates were 23% and 19% for Nd:YAG and diode laser, respectively), most patients had significant regrowth at week 36 (subjective regrowth rate 91% for both long-pulsed Nd:YAG and diode lasers).

Conclusion: Diode 800 nm and Nd:YAG 1064 nm lasers are safe in laser-assisted hair removal in Chinese patients, and besides immediate pain, there was no other significant adverse effect. Most patients experienced regrowth 36 weeks after a single treatment. Further study is necessary to determine the long-term clinical efficacy and complications of laser-assisted hair removal with these systems in dark-skinned patients.

J Cutan Laser Ther. 2000 Dec;2(4):183-90.

800 nanometer diode laser hair removal in African American patients: a clinical and histologic study.

Adrian RM, Shay KP.

Georgetown University Medical School, Center for Laser Surgery, Washington DC, USA.

BACKGROUND: Although numerous lasers are available for laser assisted hair removal, their use in individuals with a dark skin type presents many challenges due to competition from epidermal melanin. OBJECTIVE: Our aim was to evaluate two 800 nm diode lasers (Lightsheer) with 30 msec and 100 msec pulse durations in the treatment of African American patients with skin types V and VI. Histologic studies, efficacy and side effects were examined in an effort to optimize laser hair removal procedures in this patient population.
METHODS: Facial, neck and axillary areas were treated using 800 nm diode lasers at 30 and 100 msec pulse durations with fluences between 15 J/cm2 and 40 J/cm2.
RESULTS: Both lasers could be used safely in skin type V and VI African American patients. Longer pulse durations enabled the delivery of higher fluences with minor and acceptable postoperative complication profiles.
CONCLUSION: The Lightsheer diode laser (Coherent Medical, Santa Clara, CA, USA) operating at 30 msec and 100 msec can be safely used in hair removal procedures in African American patients.

PMID: 11350674

Lasers Surg Med. 2001;28(2):150-5.

Diode laser hair removal of the black patient.

Greppi I.

Celebration Institute of Aesthetic Surgery, Richard O. Gregory MD, Director Celebration, Florida 34747, USA.

BACKGROUND AND OBJECTIVE: The 810-nm wavelength diode laser can safely and successfully treat all skin types, including dark pigmented skin.
STUDY DESIGN/METHODS: Eight Fitzpatrick level V-VI skin type patients, four of which presented with the diagnosis of pseudofolliculitis barbae, were treated with the diode laser for hair removal using low-energy settings and long pulse duration.
RESULTS: All eight patients had excellent results with unwanted hair greatly reduced, and pseudofolliculitis barbae resolved.
CONCLUSIONS: Diode lasers can be used on dark pigmented skin with positive outcomes. Complications such as hypopigmentation, or hyperpigmentation occurred, but all were transient and resolved within a few months. Copyright 2001 Wiley-Liss, Inc.

Publication Types:

  • Clinical Trial

PMID: 11241522

J Cosmet Laser Ther. 2003 Dec;5(3-4):146-9.

Hair reduction: 48 months of experience with 800nm diode laser.

Kopera D.

Department of Dermatology, University of Graz, Auenbruggerplatz 8, A-8036 Graz, Austria.

BACKGROUND: The goal of hair removal methods has always been permanent or at least long-term epilation. Laser technology and the axiom of selective photothermolysis allowed a new approach to this subject.
OBJECTIVE: The aim of this retrospective study was to determine the long-term efficacy of a solid state, 800nm pulsed near infrared diode laser system for the reduction of pigmented hair, and extending habitual hair plucking intervals.
 METHODS: In 48 months 242 patients received 703 diode laser treatments on 477 sites. Treatment data and an anonymous patient questionnaire on data concerning undesired hair growth (e.g. predisposition, psychological aspects), and hair plucking habits were retrospectively evaluated to verify the benefit of 800-nm diode laser application for the reduction of excess hair.
RESULTS: After an average of 1.97 treatments (range 1-6) sufficient reduction of pigmented hair was achieved for a mean period of 8.1 months. The habitual hair plucking interval was raised from a mean of 3.69 days before treatment to 15.19 days after laser epilation. The procedure was tolerated by 81.4% without local anesthetics and well accepted by 82.55% of the patients.
CONCLUSION: 800-nm diode laser assisted hair removal represents a safe and effective treatment option for the reduction of pigmented hair.

PMID: 14741817

Arch Dermatol Res. 2000 Feb-Mar;292(2-3):60-7.

Reduction of regrowing hair shaft size and pigmentation after ruby and diode laser treatment.

Lin TY, Dierickx CC, Campos VB, Farinelli WA, Rosenthal J, Anderson RR.

Department of Dermatology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.

Laser pulses which selectively damage pigmented hair follicles are a useful treatment for hypertrichosis. Clinically, regrowing hairs are often thinner and lighter after treatment. In this study, hair shaft diameter and optical transmission (700 nm) were measured before and after ruby (694 nm) and diode (800 nm) laser irradiation. Hair was collected from 47 and 41 subjects treated with ruby (0.3 ms and 3 ms) and diode (10-20 ms) lasers, respectively. "Responders" were defined as subjects with significant long-term hair loss as determined by hair counts at 9 and/or 12 months after treatment. In ruby laser responders (34/47), regrowing hairs were significantly both thinner (decreased diameter) and lighter (increased transmission). In "nonresponders" (13/47), regrowing hairs were lighter, but not thinner. The regrowing hair shaft absorption coefficient (as calculated assuming Beer's law) was significantly decreased by 0.3 ms ruby laser treatment, but was not changed by 3 ms ruby laser or diode laser treatment. After diode laser treatment, 38 of the 41 subjects were responders and regrowing hairs were both thinner and lighter. These results show that laser treatments can affect structural recovery (size of hair), follicular pigmentation (hair absorption coefficient), or both. Regrowth of thinner hair (decreased shaft diameter) occurs in conjunction with actual loss of hair. After long pulses (3 ms ruby; diode), regrowing hair was thinner and also lighter to an extent related to the decrease in hair diameter. In contrast, short ruby laser pulses (0.3 ms) appeared to be capable of inhibiting follicular pigmentation per se, in addition to affecting the hair diameter. This may account for the complete regrowth of lighter hair in "nonresponders" treated with 0.3 ms pulses. Laser-induced reduction in hair diameter and/or pigmentation are both long-term responses which confer cosmetic benefits in addition to actual hair loss.

PMID: 10749557

J Cutan Laser Ther. 1999 Apr;1(2):109-11.

Treatment of pseudofolliculitis barbae with the diode laser.

Yamauchi PS, Kelly AP, Lask GP.

Dermatologic Laser Center, UCLA, Los Angeles, CA, USA.

Pseudofolliculitis barbae is a common skin disorder of the beard area that is characterized by the presence of inflammatory follicular papules due to terminal hair shafts re-entering the epidermis. Postinflammatory hyperpigmentation and scarring often occur with pseudofolliculitis barbae. Such skin changes can lead to cosmetic disfigurement and be of great concern to the patient. We report a case of pseudofolliculitis barbae and hirsutism with associated postinflammatory hyperpigmentation in an African-American woman who was effectively treated with the diode laser.

Publication Types:

  • Case Reports

PMID: 11357287

Phone: (757) 436-4774

Meladine™ Receives FDA Marketing Clearance as an Accessory to Hair Removal
Lasers to Treat Non-pigmented Hai

Chesapeake, VA—February 14, 2003—Creative Technologies, Inc. announced today that the U.S. Food and Drug Administration (FDA) has granted marketing clearance to Meladine™ as an Accessory to Surgical Laser Instruments used for Hair Removal. Meladine is the first product of its kind to effectively enhance the effects of hair removal lasers in treating white, gray and blonde hair.

Meladine is a proprietary melanin enhancer that supplements the natural melanin in hair. A patented liposome delivery system ensures that the pigment is able to penetrate deep into the hair follicle to provide melanin to the bulb and the bulge. The melanin deposit provides a temporary melanin-rich target in the follicle to aid the effects of the laser.

Clearance was granted based on data from a 2 year clinical study. The study included 40 adult patients, aged 28 to 75, suffering from mild to excessive non-pigmented hair growth. Each patient was pretreated with Meladine for 14 days prior to laser hair removal treatment. As a control group, 20 patients with non-pigmented hair growth received laser hair removal treatment without the use of a melanin enhancer.

Results from the study reveal that six months after the last laser treatment, 90% of the patients experienced permanent hair reduction of over 75% within 10 treatments, with an average number of 7 treatments. With an average of 8 treatments, 62.5% of the patients experienced a hair reduction of 95% or more. These results are in contrast to 0% hair reduction experienced by the control group who did not use Meladine.

In addition to FDA clearance, several recent advances have solidified Meladine’s position as an effective method for treating non-pigmented hair. At the annual meeting of the American Society for Dermatologic Surgery in November, Dr. Tina Alster and Dr. Elizabeth Tanzi of the Washington Institute of Dermatologic Laser Surgery released preliminary results from an on-going clinical trial on Meladine. Early results reveal that 1 month after the third laser treatment, 49-54% vellus hair reduction was noted in each patient studied. These results have triggered wide spread publicity of Meladine in several highly acclaimed publications such as Dermatology Times, Dermascope, Allure, and Aesthetic Buyers Guide.

“While products in the past have promised the removal of non-pigmented hair, Meladine has demonstrated lasting results time and again.” says President and CEO of Creative Technologies, Inc., Dennis R. Jones. “There isn’t a laser hair removal facility in the world that doesn’t deal with the frustration of treating white, gray and blonde hair—whether is it a patient you have to turn down because their hair is not the right color or the residual 10% vellus hairs that appear in the patient’s final treatments. We anticipate that FDA clearance will inspire the additional confidence that doctors and laser hair removal facilities need to try Meladine in their practices. Meladine is the safe and effective product that the laser hair removal industry has been waiting for”.

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