Laser Hair Removal: Comparison of Long-Pulsed Nd:YAG, Long-Pulsed Alexandrite, and Long-Pulsed Diode Lasers

Background. Advances in laser technology over the past several years have led to the development of numerous lasers for the treatment of unwanted hair. Laser wavelength is a key factor influencing treatment efficacy and complication rates.
Objective. To compare the efficacy and safety of laser hair removal using three different laser systems.
Methods. A retrospective study of 805 consecutive laser-assisted hair removal treatments, conducted on 75 patients by means of either a long-pulsed Nd:YAG, a long-pulsed alexandrite, or a long-pulsed diode laser is reported. All patients were evaluated at least 3 months after the last treatment, and their present conditions were compared with the 1st-day photographs.
Results. The mean hair reduction was 42.4%, 65.6%, and 46.9% in Nd:YAG, alexandrite, and diode lasers, respectively. When the number of treatment sessions was taken into account, the efficacy of alexandrite and diode lasers was not significantly different, whereas both systems were more efficacious than Nd:YAG. Neither of the laser systems showed better results for a particular skin type. The occurrence of side effects was not significantly different between three laser systems.
Conclusion. Both long-pulsed alexandrite and long-pulsed diode laser systems are effective in the treatment of unwanted hair, and they are more efficacious than Nd:YAG laser.     

Comparison of Long-Pulsed Diode and Long-Pulsed Alexandrite Lasers for Hair Removal: A Long-Term Clinical and Histologic Study

BACKGROUND: Unwanted facial and body hair is a common problem, generating a high level of interest for treatment innovations. Advances in laser technology over the past several years has led to the development and distribution of numerous red and infrared lasers and light sources to address this issue. Despite the impressive clinical results that have been reported with the use of individual laser hair removal systems, long-term comparative studies have been scarce. OBJECTIVE: To compare the clinical and histologic efficacy, side effect profile, and long-term hair reduction of long-pulsed diode and long-pulsed alexandrite laser systems. METHODS: Twenty women with Fitzpatrick skin types I-IV and dark terminal hair underwent three monthly laser-assisted hair removal sessions with a long-pulsed alexandrite laser (755 nm, 2-msec pulse, 10 mm spot) and a long-pulsed diode laser (800 nm, 12.5 msec or 25 msec, 9 mm spot). Axillary areas were randomly assigned to receive treatment using each laser system at either 25 J/cm2 or 40 J/cm2. Follow-up manual hair counts and photographs of each area were obtained at each of the three treatment visits and at 1, 3, and 6 months after the final laser session. Histologic specimens were obtained at baseline, immediately after the initial laser treatment, and 1 and 6 months after the third treatment session. RESULTS: After each laser treatment, hair counts were successively reduced and few patients found it necessary to shave the sparsely regrown hair. Optimal clinical response was achieved 1 month after the second laser treatment, regardless of the laser system or fluence used. Six months after the third and final treatment, prolonged clinical hair reduction was observed with no significant differences between the laser systems and fluences used. Histologic tissue changes supported the clinical responses observed with evidence of initial follicular injury followed by slow follicular regeneration. Side effects, including treatment pain and vesiculation, were rare after treatment with either laser system, but were observed more frequently with the long-pulsed diode system at the higher fluence of 40 J/cm2. CONCLUSION: Equivalent clinical and histologic responses were observed using a long-pulsed alexandrite and a long-pulsed diode laser for hair removal with minimal adverse sequelae. While long-term hair reduction can be obtained in most patients after a series of laser treatments, partial hair regrowth is typical within 6 months, suggesting the need for additional treatments to improve the rate of permanent hair removal.     

Clinical Experience with Light-Emitting Diode (LED) Photomodulation

Background. Light-emitting diode (LED) photomodulation is a novel nonthermal technology used to modulate cellular activity with light.
Objective:. We describe our experience over the last 2 years using 590 nm LED photomodulation within a dermatologic surgery environment.
Methods. Practical use of nonthermal light energy and emerging applications in 3,500 treatments delivered to 900 patients is detailed.
Results. LED photomodulation has been used alone for skin rejuvenation in over 300 patients but has been effective in augmentation of results in 600 patients receiving concomitant nonablative thermal and vascular treatments such as intense pulsed light, pulsed dye laser, KTP and infrared lasers, radiofrequency energy, and ablative lasers.
Conclusion:. LED photomodulation reverses signs of photoaging using a new nonthermal mechanism. The anti-inflammatory component of LED in combination with the cell regulatory component helps improve the outcome of other thermal-based rejuvenation treatments.     

不同类型皮肤激光脱毛效果与并发症的探讨

目的 探讨半导体激光和长脉冲翠绿宝石激光对不同类型皮肤脱毛的效果与并发症.方法 将1103例（1760部位）按皮肤类型随机分为两组;一组使用半导体激光治疗,波长810 nm,脉宽400 ms,方形光斑12 mm×10 mm;另一组使用长脉冲翠绿宝石激光治疗,波长755 nm,脉宽20 ms,光斑直径12.5 mm,2次治疗间隔时间均为50～60 d.结果 两种治疗方法对不同类型的皮肤进行脱毛治疗,效果无明显差异,但对深肤色者,半导体激光治疗的并发症发生率低.结论 两种激光对不同类型皮肤脱毛效果相似,但半导体激光对深色皮肤的脱毛更安全.     

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

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.     

Treatment of inflammatory facial acne vulgaris with combination 595-nm pulsed-dye laser with dynamic-cooling-device and 1,450-nm diode laser

BACKGROUND AND OBJECTIVES: The 585-nm pulsed-dye laser and the 1,450-nm diode laser have been found effective for the treatment of mild-to-moderate inflammatory facial acne. This study was designed to evaluate the efficacy and safety of the combined treatment with the 595-nm pulsed-dye laser and the 1,450-nm diode laser for inflammatory facial acne. STUDY DESIGN/MATERIALS AND METHODS: Fifteen patients with inflammatory facial acne were treated with a combination of the 595-nm pulsed-dye laser and the 1,450-nm diode laser. Patients' subjective response to treatment was evaluated regarding improvement in acne, acne scarring, oiliness, and redness of the skin. RESULTS: All patients had reductions in acne lesion counts. Mean lesion counts decreased 52% (P < 0.01), 63% (P < 0.01), and 84% (P < 0.01) after one, two, and three treatments, respectively. Patients described moderate-to-marked improvement in acne, acne scarring, and post-inflammatory erythema. Adverse effects were limited to mild, transient erythema. CONCLUSIONS: The combination of the 595-nm pulsed-dye laser and the 1,450-nm diode laser is safe and effective for the treatment of inflammatory facial acne, acne scarring, and post-inflammatory erythema.     

Results of nonablative wrinkle reduction with a 1,450-nm diode laser: difficulties in the assessment of "subtle changes"

BACKGROUND AND OBJECTIVE: Nonablative resurfacing has proven its efficacy in vascular and pigmented lesions, while its capacity of substantial wrinkle reduction is still discussed controversially. We present the treatment results of a 1,450 nm diode laser for facial rhytides. METHODS: Thirty facial regions were treated with a 1,450 nm diode laser. Pre- and post treatment pictures were compared by the treating physician and two blinded observers. RESULTS: Even if mild improvement was rated in up to 35% of the post treatment pictures, a discrepancy shows up in the assessments of the three observers, presenting almost no congruency in the rating of improvement. CONCLUSIONS: Our study failed to provide convincing data on the efficacy of nonablative treatment of rhytides with the 1,450 nm diode laser. In this respect, we challenge objective judgment in the assessment of subtle changes in nonablative wrinkle reduction.     

Nonablative laser and light therapies for skin rejuvenation

BACKGROUND: Multiple modalities have been described for skin rejuvenation, including ablative and nonablative therapies. Because of the prolonged recovery period associated with ablative procedures that injure the epidermis, nonablative skin treatments have grown increasingly popular. Various laser- and light-based systems have been designed or applied for promoting skin remodeling without damage to the epidermis. METHODS: Studies investigating the use of nonablative procedures for facial rhytids or acne scarring with clinical, histological, and objective quantitative measurements are systematically reviewed. RESULTS: Nonablative treatments are associated with clinical and objective improvements for the treatment of facial rhytids and acne scarring. Dermal remodeling seems to occur as a result of thermal injury, leading to dermal fibrosis without epidermal disruption. CONCLUSIONS: Although results are not as impressive as those of ablative treatments, nonablative procedures are effective in the treatment of photoaging and acne scarring. As technology in nonablative therapies continues to evolve, future laser and light sources may yield even more favorable results.     

Hair Removal Using Topical Suspension-Assisted Q-Switched Nd:YAG and Long-Pulsed Alexandrite Lasers: A Comparative Study

Background. The use of lasers for removal of unwanted hair has been shown to be effective in temporarily controlling hair growth. Several lasers are currently utilized for this purpose.
Objective. This study evaluates the short-term effectiveness and discomfort levels of the long-pulsed alexandrite laser and the topical suspension-assisted Q-switched Nd:YAG laser in a side-by-side comparison.
Methods. Fifteen subjects were treated in the bilateral hair-bearing axilla, using one treatment with the alexandrite laser for the right and two treatments with the topical suspension-assisted Nd:YAG laser for the left. Reduction in hair regrowth was measured at 2 and 3 months following the first treatment by comparing the terminal hair count to the baseline values. Patients rated their pain on a scale of 0–10 immediately following the first treatment at each site.
Results. The mean percentage reduction in hair regrowth 2 months following alexandrite laser treatment was 55% and 73% for the Nd:YAG laser-treated regions. After 3 months, alexandrite laser-treated patients showed a reduction of 19%, while Nd:YAG laser-treated patients showed a 27% reduction. Patients reported average pain values of 8 and 4 for the long-pulsed alexandrite and Nd:YAG laser sites, respectively. All differences were significant.
Conclusion. While the design of this study makes it difficult to compare the relative effectiveness of the lasers, both systems evaluated were shown to delay hair growth and provide patients with a satisfactory treatment.     

Intense pulsed light and Nd:YAG laser non-ablative treatment of facial rhytids

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the efficacy and safety of the intense pulsed light source (IPL) and the Nd:YAG laser in the treatment of facial rhytids. Both systems can be used in a non-ablative manner and cause a dermal wound. This is thought to stimulate the production of new collagen without epidermal disruption. Non-ablative techniques eliminate the downtime that must be endured by patients treated with ablative methods such as the carbon dioxide and erbium lasers. STUDY DESIGN/MATERIALS AND METHODS: Fifteen subjects with perioral rhytids and Fitzpatrick skin types II and III received three-to-five treatments with the IPL using 590 and 755 nm cut-off filters, and the 1,064-nm Nd:YAG laser. The subjects were evaluated at 2, 4, 8, 12, and 24 weeks after the final treatment for improvement in rhytids and presence of any side effects. RESULTS: At 6 months, the patient satisfaction score (1-10) was comparable in all three groups. Evaluator assessment of improved skin quality was also similar in all three treatment groups. Side effects such as blistering and erythema were most commonly seen in the subjects treated with the IPL. The least discomfort was seen with the Nd:YAG laser. CONCLUSIONS: Although both non-ablative treatment systems improved facial rhytids presumably by causing a non-specific dermal wound, the Nd:YAG laser was better tolerated and produced fewer side effects.     

Comparative Evaluation of Long-Pulse Alexandrite and Long-Pulse Nd:YAG Laser Systems Used Individually and in Combination for Axillary Hair Removal

BACKGROUND The 755-nm alexandrite and the 1,064-nm Nd:YAG lasers are both utilized for hair removal. Advances in laser technology have led to the development of dual-wavelength treatment for increased efficacy.
OBJECTIVE The objective was to evaluate the safety and efficacy of combining 755- and 1,064-nm wavelengths for axillary hair removal.
METHODS Twenty patients received three treatments at 4- to 6-week intervals in four axillary quadrants. The left upper axilla was treated with the alexandrite laser, the left lower axilla with the Nd:YAG laser, the right upper axilla with combination alexandrite and Nd:YAG laser, and the right lower quadrant with the diode laser. At 1- and 2-month follow-up visits, subjects completed questionnaires and were assessed for percentage of hair reduction.
RESULTS Eighteen subjects completed the study. The greatest reduction was seen with the alexandrite laser at 70.3% and combination of alexandrite and Nd:YAG laser at 67.1%. The diode laser was less efficacious at 59.7% and the Nd:YAG laser had the least improvement with 47.4% reduction. Subjects found the alexandrite and diode lasers to be the most tolerable and the Nd:YAG and combination treatment to be the most painful.
CONCLUSION Combination treatment of alexandrite and Nd:YAG lasers provides no added benefit over the alexandrite laser alone.     

Hair Growth Induced by Diode Laser Treatment

BACKGROUND: Although hair reduction by long-pulsed red and infrared lasers and light sources is generally quite effective, paradoxical hair growth has rarely been observed following treatment. OBJECTIVE: To report a case of thick hair growth following 810 nm diode laser treatment and its subsequent treatment. METHODS. A 24-year-old man who had previously had laser hair reduction on his posterior neck was treated to a test area on his upper back. RESULTS: Thick terminal hair developed in the treated area subsequent to laser treatment. Further treatment of this area removed the terminal hair but resulted in terminal hair growth in an annular distribution surrounding the treatment site. CONCLUSIONS: Diode laser treatment rarely stimulates terminal hair growth. This phenomenon should be studied to better understand hair growth cycles and to help develop more effective treatments for hair loss and hair growth.     

The Effect of Different Spot Sizes on the Efficacy of Hair Removal Using a Long-Pulsed Diode Laser

BACKGROUND: In the last years several lasers have proven their efficacy for hair removal. However, little is known about the efficacy of varying the spot size with those lasers. OBJECTIVE: To evaluate the long-term efficacy of hair removal using a diode laser with different spot sizes. METHODS: A long-pulsed diode laser (2 x 60 msec) was used. The spot size was 8 mm, 12 mm, or 14 mm. Twenty consenting volunteers were treated three times at regular intervals of 3 weeks. The ratio of the number of hairs in the treated area to an adjacent area left untreated (control) was referred to as regrowth. RESULTS: One month after laser treatment, regrowth was 23% (8 mm), 12% (12 mm), and 13% (14 mm). After 3 months regrowth was 67% (8 mm), 54% (12 mm), and 55% (14 mm). Fifteen months after treatment 4 of 16 volunteers had a regrowth rate of less than 25%. CONCLUSION: The results provide evidence for an effective and long-lasting growth delay of hairs using the long-pulsed diode laser. The use of large spot sizes improved the growth delay of hairs measured 1 month after treatment.     

Q-Switched Alexandrite Laser-induced Chrysiasis

Background: Chyriasis is an uncommon side effect that occurs in patients who are receiving prolonged treatment with either intravenous or intramuscular gold as a distinctive blue-gray pigmentation of light-exposed skin. Laser-induced chrysiasis is a rarely described phenomenon in individuals who have received systemic gold and are subsequently treated with a Q-switched laser. Purpose: To describe the characteristics of patients with laser-induced chrysiasis. Methods: The authors describe a 60-year-old woman who developed chrysiasis at Q-switched alexandrite laser treatment sites. They also reviewed the medical literature using PubMed, searching the terms chrysiasis, gold, and laser-induced. Patient reports and previous reviews of these subjects were critically assessed and the salient features are presented. Results: Including the authors’ patient, laser-induced chrysiasis has been described in five Caucasian arthritis patients (4 women and 1 man); most of the patients had received more than 8g of systemic gold therapy during a period of 3 to 13 years. Gold therapy was still occurring or had been discontinued as long as 26 years prior to laser treatment. All of the patients immediately developed blue macules at the Q-switched laser treatment site. Resolution of the dyschromia occurred in a 70-year-old woman after two treatment sessions with a long-pulsed ruby laser and the authors’ patient after a sequential series of laser sessions using a long-pulsed alexandrite laser, followed by a nonablative fractional laser and an ablative carbon dioxide laser. Conclusion: Laser-induced chrysiasis has been observed following treatment with Q-switched lasers in patients who are receiving or have previously been treated with systemic gold. It can occur decades after treatment with gold has been discontinued. Therefore, inquiry regarding a prior history of treatment with gold—particularly in older patients with arthritis—should be considered prior to treatment with a Q-switched laser. Also, treatment with a long-pulsed laser should be entertained in patients with either idiopathic or laser-induced chrysiasis. (JClinAesthetDermatol. 2015;8(9):48-53.)Chrysiasis is a distinctive blue-gray pigmentation of light exposed skin occurring in individuals who are receiving parenteral gold therapy.1 The 755nm Q-switched alexandrite laser is effective for the treatment of facial lentigines since the melanin granules absorb a high proportion of the laser energy and other chromophores offer little competitive absorption.2 The authors describe a woman who developed chrysiasis at Q-switched alexandrite laser treatment sites and whose dyschromia was successfully treated with a sequential series of laser sessions using a long-pulsed alexandrite laser, followed by a nonablative fractional laser and an ablative carbon dioxide laser.     

Facial rejuvenation and light: our personal experience

The treatment of ageing skin remains a very hot topic, and many systems have been reported as having varying degrees of success. Nonablative lasers were developed to avoid the problematic and uncomfortable sequelae following laser ablative resurfacing, and while there was no downtime, there was also poor patient satisfaction. The same was true of the intense pulsed light systems. The use of different modalities in various combinations was found to offer much better results, however, such as a 595-nm pulsed dye laser followed by a 1,450-nm diode laser, and so on, all used at subablative thresholds. The recent entry of blue and infrared tunable plasma light and light-emitting diodes into the skin rejuvenation arena has attracted a great deal of attention. The authors suggest that no single modality can accomplish all the complex events required for effective skin rejuvenation, suggest that combination phototherapy is the best approach combined with an adjunctive epidermal care regimen, and demonstrate their development of this methodology.     

Successful Treatment of a Chronic Atrophic Dog-Bite Scar with the 1450-nm Diode Laser

BACKGROUND: Atrophic scars can be revised with surgical methods and more recently with newer ablative and nonablative laser techniques. Nonablative laser technology offers the advantage of improving the appearance of atrophic scars without the risks associated with traditional surgery or ablative lasers. METHODS: A case of a large linear atrophic dog-bite scar on the chin of greater than 2-year duration treated for three sessions at 4- to 6-week intervals with the 1450-nm diode laser is presented. RESULTS: Fifty to seventy-five percent improvement in the appearance of the scar resulted after three treatments with the 1450-nm diode laser. No adverse effects were noted from the treatment. The patient subjective rating of scar improvement was more than 50%. CONCLUSION: The 1450-nm diode laser may provide a noninvasive and effective alternative for the treatment of atrophic traumatic scars. This method appears to be potentially effective even for treatment of very mature scars and warrants additional studies.     

Nonablative resurfacing

In expert hands, ablative laser resurfacing has a long history of excellent results in the treatment of photodamage-induced rhytids, depressed acne scars, and other signs of cutaneous aging. Over the last decade there have been a growing number of reports in the emerging area of nonablative resurfacing. Nonablative modalities provide less impressive clinical results for rhytid reduction but have shown particular promise for the treatment of scars and superficial dyschromias. It is also ideally suited for those patients seeking a minimally invasive, greatly reduced downtime procedure.     

Comparison of short-pulsed and long-pulsed 532 nm lasers in the removal of freckles

The purpose of this study was to compare the efficacy and safety of the 532 nm long-pulsed laser (10 ms) with that of the 532 nm short-pulsed laser (10 ns) for freckle removal. Currently, the gold standard for treatment is the short-pulsed laser. Recently, several long-pulsed lasers have been introduced for both hair removal and the treatment of freckles. To our investigative team’s knowledge, no controlled experiments have been performed to compare the safety and efficacy of long-pulsed versus short-pulsed lasers for the treatment of freckles. This was a 4-week trial, and all patients had three freckles that were randomly allocated to be treated with short-pulse laser, long-pulse laser, or to receive no treatment (control). All patients had three freckles that were randomly selected to be treated with short-pulse 532 nm Medlite IV laser (10 n, 1 J/cm²), or long-pulse 532 nm Aura laser (10 ms, 1 J/cm²) or to remain as a control (no treatment). The laser treatment was only performed once, followed by a 1-day and a 1-month follow-up visit. Freckle size was determined by a novel surface area measurement technique that was created by our research staff. The study included 17 sets of freckles (three in each set). All of the lesions which received the short-pulsed laser treatment had immediate whitening of the lesions, which turned into dry scabs the next day. None of the freckles treated in the long-pulsed group or control group developed immediate whitening or scabs. No blisters or ulcers developed. The average pain score in the short-pulsed laser group was 2–3 out of 10, while it was 0 out of 10 in the long-pulsed laser group. All scabs that developed in the short-pulsed laser group fell off between days 6 and 12 (average 8 days). The outcome of this study verified the appropriate treatment of freckles. The study confirmed that when the same energy settings, short-pulsed laser is the more effective laser treatment regimen (when compared with the long-pulsed laser), with high tolerability and minimal side effects for patients with skin types I to IV.     

Clinical Evaluation of a 1,450-nm Diode Laser as Adjunctive Treatment for Refractory Facial Acne Vulgaris

BACKGROUND Despite aggressive multitreatment medical acne regimens, many patients demonstrate modest benefit. The 1,450-nm diode laser has been shown to improve acne in a study setting.
OBJECTIVE Herein we evaluate the use of this laser as an adjunctive tool in the management of refractory facial acne vulgaris.
MATERIALS AND METHODS Thirteen patients were treated. Lesion counts, clinical evaluation, and digital photography were performed at baseline and at all follow-up visits. Patients received an average of three treatments. Acne severity index and patient satisfaction were assessed. Patients continued their medical acne regimen where applicable.
RESULTS Mean total lesion and inflammatory lesion counts decreased from 66 ± 14 and 23 ± 5 at baseline to 34 ± 12.9 and 14 ± 7 after three treatments ( p <.05). Side effects were mild, including erythema lasting up to 24 hours.
CONCLUSION The 1,450-nm diode laser provides moderate improvement of refractory acne vulgaris. Our findings support the use of this device as an adjunctive treatment for acne management.     

Facial rhytides—subsurfacing or resurfacing? A review

STUDY DESIGN/BACKGROUND AND OBJECTIVES: Currently, ablative laser therapy (with CO2/Er:YAG lasers) is considered an effective and promising method of skin rejuvenation. The induction of collagen synthesis was observed after treatments with the CO2 laser and with the long-pulsed Er:Yag laser. In past years, the undesirable side effects and risks of these methods have led to intensified research efforts in the fields of non-ablative facial rejuvenation as well as subsurfacing by means of non-ablative laser systems and intense pulsed light systems. The objective is to achieve selective, heat-induced denaturalization of dermal collagen that leads to subsequent reactive synthesis of neocollagen but does not damage the epidermis. This article reviews the use of different types of lasers and intense pulsed light sources for the non-ablative treatment of facial rhytides. RESULTS: The results of numerous clinical and histological investigations have recently indicated that these new technologies are successful. Some studies demonstrated remarkable effects with non-ablative systems; others, however, showed only limited cosmetic improvement or none at all. CONCLUSIONS: After critical review and assessment of current literature on the treatment of rhytides, we have found that non-ablative methods do not appear to be a comparable alternative to ablative skin resurfacing in terms of their efficacy and side effects.