Evaluation of the safety and efficacy of the dual wavelength picosecond laser for the treatment of benign pigmented lesions in Asians.

BACKGROUND AND OBJECTIVES: Cutaneous pigmentary disorders are both more common and more difficult to treat in patients with skin color given the higher melanin content in the epidermis. Although Q-switched lasers are widely considered to be the standard treatment for both epidermal and dermal pigmentary conditions, a very high risk of post-inflammatory hyperpigmentation (PIH) of up to 25% is seen in patients with skin of color. Recently, the novel picosecond laser with pulse durations operating at sub-nanosecond domains has been shown to be effective in tattoo removal and in the treatment of acne scars. The objective of this study is to examine the safety and efficacy of the dual wavelength picosecond laser for the treatment of benign pigmented skin lesions in Asian patients. METHODS: Twelve subjects with benign pigmentary disorders and Fitzpatrick skin types III to IV were recruited in a prospective clinical study to examine the safety and efficacy of the dual wavelength picosecond laser. Patients were treated at approximately 2-6 week intervals depending of the type of lesion. The primary efficacy endpoint is the global percent of clearance which was evaluated by blinded observers using post treatment photographs compared to baseline photographs. Safety was evaluated before and after each laser treatment and patients were asked to rate the level of pain according to the Visual Analog Scale after each treatment session. Patient satisfaction was assessed at the completion of treatment with questionnaires. All patients were followed up at 4, 8, and 12 weeks after the last treatment session. RESULTS: The pigmentary conditions treated included melasma, freckles, lentiginies, café au lait macules, and Hori's macules. Three months after treatment, 53.8% of all pigments achieved excellent response (75-94% lightening,) 30.8% of pigments achieved good response (50-74% lightening,) and 7.7% of pigments achieved both fair (25-49% lightening) and poor responses (0-24% lightening), respectively. The average number of treatment sessions required to reach at least 50% clearance was 4.5 for melasma, 1 for freckles, 1.5 for lentigines and 1 for café au lait. The patient with Hori's macules did not reach 50% clearance after a total of six treatments. Sixty three percent of patients reported satisfaction in the subjective assessment, while 27.3% were neutral and 9.1% were very dissatisfied. The post inflammatory hyperpigmentation rate was 4.8% and 6.5% of subjects developed blistering as a side effect of treatment. CONCLUSION: The dual wavelength picosecond laser is a safe and effective treatment of benign pigmentary conditions in patients with skin of color. In particular, superior clinical efficacy is demonstrated for treatment of freckles and lentigines with a low risk of PIH. Lasers Surg. Med. 51:14-22, 2019. © 2018 Wiley Periodicals, Inc.

A case series of facial depigmentation associated with low fluence Q-switched 1,064 nm Nd:YAG laser for skin rejuvenation and melasma.

BACKGROUND AND OBJECTIVE: In recent years, "laser toning" using low fluence, large spot size, multiple passed Q-switched 1,064 nm Nd:YAG laser has gained much popularity in Asian countries for non-ablative skin rejuvenation and the treatment of melasma. This case series highlights one of the complications associated with laser toning, which is facial depigmentation. MATERIALS AND METHODS: Fourteen patients with laser toning-associated facial depigmentation were assessed with cross-polarized and ultraviolet (UV) photographic images. The laser toning regimens received by these patients, as well as the treatment given for depigmentation, were analyzed retrospectively. RESULTS: All 14 patients were Chinese females, 9 of whom received laser toning for non-ablative skin rejuvenation and the other 5 for melasma. The treatment regimens received by these patients were highly variable. The total number of treatments received ranged from 6 to 50 (mean 22.07). In all cases, UV photographic images demonstrated facial mottled depigmentation. Laser toning failed to significantly improve melasma in all five patients. Five patients received targeted narrowband UVB for depigmentation with good clinical results. CONCLUSIONS: Laser toning with low fluence Q-switched 1,064 nm Nd:YAG laser for skin rejuvenation and melasma can be associated with mottled depigmentation. With laser toning being frequently performed, this complication may become more commonly encountered in clinical practice. The depigmentation can appear after only a few treatment sessions, and can cause much disfigurement, especially in cases with background melasma. Further studies on laser toning are needed with the view to optimizing efficacy and minimizing side-effects.

The use of non-ablative fractional resurfacing in Asian acne scar patients.

BACKGROUND AND OBJECTIVES: Non-ablative fractional resurfacing (NA FR) has been shown to be effective for photorejuvenation and acne scarring. Previous studies indicated that density, more than pulse energy, was associated with post-inflammatory hyperpigmentation (PIH) in Asians. The objective of this retrospective study was to assess the efficacy and complications of eight passes of NA FR ('full-NA FR') with the 1,550 nm erbium-doped fibre fractional laser (Fraxel SR laser system, Solta Medical, Hayward, CA) versus four passes ('mini-NA FR') with comparable pulse energy and treatment level as 'full-NA FR', but double the number of treatment sessions in Asian acne scar patients. MATERIALS AND METHODS: Forty-seven Asian atrophic facial acne scar patients who received full-face full-NA FR or mini-NA FR treatments between December 2005 and February 2009 were included. All photographic images captured with the Canfield Visia CR system at baseline and follow-ups were assessed for clinical efficacy and complications by an independent, non-treating and blinded physician. RESULTS: The total treatment densities for full-NA FR and mini-NA FR were 442.5 and 210.5 MTZ/cm(2), respectively. For full-NA FR, the PIH risk was 18.2% with cross-polarized images compared to 6.0% for mini-NA FR. This difference was statistically significant (P < 0.001). Improvement in skin texture, acne scarring, enlarged pores and overall pigmentation irregularity all reached statistical significance at last follow-up compared to baseline. There was no statistically significant difference in clinical efficacy between three full-NA FR and six mini-NA FR treatments. CONCLUSIONS: NA FR was effective and safe in Asians. By reducing the number of passes and the total treatment density, the risk of PIH could be reduced. Meanwhile, clinical efficacy could be maintained by increasing the total number of treatment sessions.

Combined infrared light and bipolar radiofrequency for skin tightening in Asians.

BACKGROUND AND OBJECTIVE: As the demand for non-invasive procedures for skin tightening is increasing, combined optical and radiofrequency (RF) devices have recently emerged. The purpose of this study is to evaluate the safety and efficacy of a device that combined broadband infrared (IR) light (700-2000 nm) and bipolar RF (electro-optical synergy [ELOS]) for non-ablative treatment of facial laxity. DESIGN/MATERIALS AND METHODS: Nineteen Chinese volunteers of skin types III-V, with facial laxity and periorbital rhytides, received three treatments at 3-week intervals with combined IR (700-2000 nm, 10 W/cm(2)) and RF energies (70-120 J/cm(3)). Standardized photographs were taken by the Canfield Visia CR system at baseline and serially for 3 months after the last treatment. Two masked assessors evaluated the photographs to assess the improvement in skin laxity. Patient satisfaction scores were also obtained. RESULTS: At 3 months after the last treatment, 89.5% of the subjects reported moderate to significant subjective improvement in skin laxity of cheek, jowl, periorbital area and upper neck, with a high overall satisfaction rating. Masked observers' assessments were less remarkable. Mild improvement in skin laxity was observed over mid and lower face. There was no serious complication. CONCLUSION: The combination of broadband infrared light and bipolar radiofrequency produces mild improvement of facial laxity in Asians with no serious adverse sequelae. A high patients' satisfaction is achieved. However, further studies are necessary to demonstrate the long-term effects of the procedure and to optimize treatment parameters.

A comparative study of intense pulsed light alone and its combination with photodynamic therapy for the treatment of facial acne in Asian skin.

BACKGROUND AND OBJECTIVES: The reaction to intense pulsed light (IPL) on Asian skin often differs from that on Caucasian skin. The study reported herein evaluated the effect on acne vulgaris of IPL alone and when IPL was combined with photodynamic therapy (PDT) using topical methyl aminolevulinate (MAL) in Asians. STUDY DESIGN/MATERIALS AND METHODS: Thirty Chinese subjects with phototypes IV or V and moderate acne were enrolled for a randomized, half-facial treatment study with IPL alone, IPL with PDT, or as controls. Sixteen percent MAL cream was applied to half of the face 30 minutes before treatment in the PDT group. The IPL was provided by the Ellipse Flex system (Danish Dermatologic Development, Denmark), which emitted wavelengths of 530 to 750 nm. The subjects were treated four times at 3-week intervals. Single passes of double pulses with a 10 milliseconds delay and a pulse duration of 2.5 milliseconds were used. The assessment of inflammatory and non-inflammatory acne lesions by two blinded investigators was based on standardized photographs that were taken before each treatment, and at 4 and 12 weeks after the final treatment. RESULTS: Twenty-three patients completed the study. The mean reduction of the inflammatory lesion count was 53% in the PDT group, 22% in the IPL group, and 72% in the control group at 4 weeks, and 65% in the PDT group, 23% in the IPL group, and 88% in control group at 12 weeks. The mean clearance of non-inflammatory lesions was 52% in the PDT group, 15% in the IPL group, and 14% in the control group at 4 weeks, and 38% in the PDT group and 44% in the IPL group at 12 weeks, when and an increase of 15% was noted in the control group. Most patients experienced a reduction of inflammatory lesions that was not statistically significant on the PDT-treated side (P = 0.06) or the IPL-treated side (P = 0.82) at 12 weeks after treatment. Pretreatment with MAL resulted in a better clearance of inflammatory acne than IPL alone. There were no statistically significant differences between the intervention groups and the control group in the mean reduction of inflammatory lesions. Significant reductions of non-inflammatory lesions were observed in the MAL-PDT group (38%, P = 0.05) and IPL groups (43%, P = 0.00) 12 weeks after treatment. Twenty-five percent of the subjects in the PDT group withdrew because of intolerance to procedure-related discomfort. CONCLUSIONS: MAL-PDT using IPL and MAL in Asians did not lead to significant improvement of moderate inflammatory acne compared with the control group. However, there was a delayed effect on non-inflammatory lesions, with significant reductions in both the PDT and IPL groups. A proportion of patients could not tolerate the discomfort that was related to PDT despite the short MAL incubation.