Correlation between the efficacy of picosecond-domain laser treatment for solar lentigo and the vascularity in the upper dermis using optical coherence tomography angiography in Asian women.

OBJECTIVES: The purpose of this study was to noninvasively confirm the characteristics of the dermal vasculature in patients with solar lentigo (SL) and determine any association with the efficacy of picosecond-domain laser (PSL) treatment. METHODS: Thirteen facial SL lesions in 11 Asian female patients were included in this study and evaluated over 12 weeks. An Nd:YAG laser was used at 532 nm and 750 ps. Skin color and morphological structure were evaluated by ANTERA-3D® and optical coherence tomography (OCT), respectively. To analyze the vascularity in the upper dermis, an OCT angiography (OCTA) algorithm was applied to the OCT data. RESULTS: After PSL treatment, significant improvement in both hyperpigmentation and abnormally thickened epidermis was observed, but the efficacy varied for each lesion. There was a significant correlation between the change in the melanin index due to PSL treatment and preoperative vascular density in the upper dermis. CONCLUSIONS: To the best of our knowledge, this is the first report to demonstrate a correlation between the efficacy of PSL treatment of SL lesions and the vascularity in the upper dermis. Methods to evaluate the vasculature in the upper dermis may be useful for preoperative prediction of the efficacy of PSL treatment for SL lesions.

Picosecond 755-nm alexandrite laser treatment for oral lentiginosis in Peutz-Jeghers disease.

We present the case of a 16-year-old boy with Peutz-Jeghers disease with successful treatment of oral lentiginosis with one session of picosecond 755-nm alexandrite laser. To date, only in one other article picosecond laser is used for lentiginosis in Peutz-Jeghers disease. Other therapeutical options include Q-switched 755-nm alexandrite, 1064-nm Nd:YAG, 532-nm KTP-laser, ruby and intense pulsed light, which generally require more sessions, are less pigment-selective and have overall worse results than picosecond laser treatment.

Laser therapy and light sources for labial lentigines in patients with Peutz-Jeghers syndrome.

Labial lentigines associated with Peutz-Jeghers syndrome are challenging and represent a cosmetic problem. Laser and intense-pulsed light sources (IPLS) can be used to treat these macules. However, there are few guidelines regarding the different types of protocols found in the literature. Thus, the purpose of this study was to review the pertinent literature on lasers and IPLS as therapy for labial lentigines in patients with Peutz-Jeghers syndrome. A detailed literature search was conducted in seven databases (Cochrane Library, Embase, Lilacs, PubMed, SciELO, Scopus and Web of Science) to November 2020. Data were extracted and analyzed from selected studies including study design, sample size, participants' skin color, age, and gender, parameters of the laser or IPLS used, interval and total sessions of laser application, results obtained, follow-up time and side effects. Thirteen out of 124 published studies met our eligibility criteria, covering 81 patients. Ten types of lasers and IPLS were used, and most of the sample (n = 57) was treated with Q-switch Alexandrite Laser (QSAL). The total number of sessions ranged from 1 to 12 and the interval between sessions ranged from 2 to 16 weeks. All studies have shown satisfactory results, with no further complications. The follow-up ranged from 2 to 97 months. Laser therapy and IPLS are effective in the treatment of lentigines associated with PJS. Although QSAL was used in 70.3% of the sample, different types of lasers showed comparable satisfactory results.

Randomized, evaluator-blinded comparative study of a potassium titanyl phosphate (KTP) 532-nm picosecond laser and an alexandrite 755-nm picosecond laser for the treatment of solar lentigines in Asians.

BACKGROUND: Various pigment-specific lasers can be used to treat solar lentigines. However, the most effective treatment options remain to be explored to reduce complications, such as postinflammatory hyperpigmentation, especially in dark-skinned patients. OBJECTIVES: This study aims to compare the efficacy and safety between the KTP 532-nm picosecond laser and the alexandrite 755-nm picosecond laser for the treatment of solar lentigines in Asians. MATERIALS AND METHODS: Thirty patients who had at least two solar lentigines on their arms were enrolled. A total of 30 paired lentiginous lesions were randomly selected for a single treatment with either a KTP 532-nm picosecond laser or an alexandrite 755-nm picosecond laser. Mean luminance score (L*) was evaluated at baseline and at 6 and 12 weeks to determine treatment efficacy. Improvement was assessed by a blinded physician using a 5-point score. Satisfaction was rated by patients using a visual analog scale. All adverse events were documented. RESULTS: All 30 patients completed the study. Both lasers showed significant improvement in mean L* from baseline (p < 0.001). With the parameter settings employed, lesions treated with the alexandrite 755-nm picosecond laser showed greater improvement in mean L* when compared with treatment with the KTP 532-nm picosecond laser at 12 weeks follow-up (p = 0.002). According to physician scoring, more than 50% improvement was observed in 25 and 19 lesions of the alexandrite 755-nm picosecond laser group and the KTP 532-nm picosecond laser group, respectively. Adverse events did not differ between groups. A significantly higher satisfaction score was observed with the alexandrite 755-nm picosecond laser at the last visit (p = 0.038). CONCLUSION: Both types of picosecond laser may be used to treat solar lentigines. Proper treatment settings and endpoint observation are the most important factor to achieve a successful outcome.

Cutaneous Photoaging: A Notable Pattern of Distribution of Lentigines on the Face.

Importance: Facial lentigines are a common patient complaint encountered in general and cosmetic dermatology practices. Lentigines are a marker of photoaging and understanding their distribution will provide insight into the aging process in order to better counsel patients. Objectives: To compare the relative distribution of lentigines in facial cosmetic subunits. Methods: We reviewed clinical photographs of patients receiving Alexandrite laser treatment for facial lentigines during the time period 11/1/2017-12/1/2018. Individual lentigines were plotted for each patient into one of 21 aesthetic units. A "heat map" was created to compare the relative density of these lesions. Results: Grouped peripheral cosmetic subunits contained more lentigines compared to grouped central cosmetic units. The mean number of lentigines in the central units was 0.60 and in the peripheral units was 0.85. This finding was statistically significant with a p value of 0.0001. J Drugs Dermatol. 2020;19(7): doi:10.36849/JDD.2020.5193.

A Prospective, Split-Face, Randomized Study Comparing Picosecond to Q-Switched Nd: YAG Laser for Treatment of Epidermal and Dermal Pigmented Lesions in Asians.

BACKGROUND: Whether picosecond lasers outperform Q-switched lasers in treating pigmented lesions has not been clearly evaluated. OBJECTIVE: To compare the efficacy and safety of picosecond and Q-switched lasers in treating epidermal and dermal pigmented lesions in Asians. METHODS: Eight subjects with lentigines and 6 subjects with acquired bilateral nevus of Ota-like macules were enrolled. Subjects was randomly treated with a picosecond laser on one side of the face and a Q-switched laser on the other side. Subjective assessments on pigment clearance, and adverse effect were obtained at Weeks 0, 4, 12, and 24 after the final treatment. RESULTS: Clinical improvement differed between the 2 laser systems at Week 4 (p = .034), Week 12 (p = .039), and Week 24 (p = .027), with 85.7% of picosecond and 57.2% of Q-switched laser sites showing >50% improvement at 6 months. There was no significant difference in the incidence of side effect and healing time, but picosecond laser was significantly associated with a lower treatment discomfort (p = .05). CONCLUSION: The picosecond laser seems to be more effective and better tolerated than Q-switched laser for the treatment of pigmented lesions in Asians.

Retrospective photographic review of nontattoo indications treated by picosecond laser.

BACKGROUND: Picosecond (PS) lasers were approved by the US FDA in 2012 after being shown to remove tattoos with more success and fewer treatments compared with traditional methods. PS lasers were shown to be versatile, indicated for the treatment of lentigines, café-au-lait macules (CALMs), and acne scars and skin rejuvenation. OBJECTIVE: We report our experience treating our patients for different indications using a PS laser. METHODS: We performed a retrospective chart and photographic review of all patients seen between 2016 and 2018 that were treated in our centers with a PS laser for nontattoo indications. Clinical outcomes were evaluated using side-by-side comparisons of the clinical photographs by two blinded, independent physicians using a visual analog scale consisting of six levels of treatment response. RESULTS: A total of 233 patients were studied. Most sought treatment for solar lentigo (27%) and skin rejuvenation (14%). Epidermal nevi exhibited the greatest improvement with treatment, while acne scarring demonstrated the least. Only 24% of patients experienced noteworthy, transient adverse effects. CONCLUSION: Picosecond lasers were efficacious and safe for a variety of indications. They were effective in treating epidermal nevi and pigmented lesions, such as Lentigines and CALMs.

A prospective, randomized, double-blinded, split-face pilot study comparing Q-switched 1064-nm Nd:YAG versus 532-nm Nd:YAG laser for the treatment of solar lentigines.

Treating photoaging with laser technologies has increased in popularity due to their efficacy, minimal downtime, and side effects. New Q-Switched (QS) Nd:YAG lasers' frequency doubled with 532 nm wavelength can both target epidermal chromophores as well as stimulate collagen production. The objective of this study was to compare single-pulsed 1064-nm Nd:YAG with dual-pulsed 532-nm/1064-nm QS laser for reducing solar lentigines. Ten subjects with solar lentigines were enrolled in this prospective, randomized, double-blind, split-face study. Subjects received six laser treatments (half-face dual, half single) at 2-week intervals. Blinded investigator and subject assessments were conducted 1 month posttreatment to evaluate global skin improvement, safety, and patient satisfaction. Blinded investigator assessments showed statistically significant improvement in the dual-treated side. Patient satisfaction was also statistically significantly increased in the dual-treated side. In conclusion, dual laser treatment can result in superior and safe global improvement of photoaging.

The Clinical and Histological Effect of a Low-Fluence Q-Switched 1,064-nm Neodymium: Yttrium-Aluminum-Garnet Laser for the Treatment of Melasma and Solar Lentigenes in Asians: Prospective, Randomized, and Split-Face Comparative Study.

BACKGROUND: The low-fluence Q-switched 1,064-nm neodymium:yttrium-aluminum-garnet laser (QSNYL) is popular for melasma treatment among Asians. OBJECTIVE: This study was to evaluate the clinical and histological effects of the low-fluence QSNYL for treatment of melasma and solar lentigenes. MATERIALS AND METHODS: In this randomized split-face clinical study, 22 patients with melasma or solar lentigo received low-fluence QSNYL weekly for 10 sessions on one cheek. The treatment efficacy was determined by Mexameter skin colorimetry, physician and patient assessment, and by evaluating histological changes. RESULTS: The treated sides had statistically significant reductions in the melanin and erythema indices (EI); 50.0% of melasma and 62.5% of solar lentigo patients had >50% clearance after the final treatment. The increased EI, vascularity, and mast cell activity in patients with melasma and large-sized solar lentigo showed no improvement. The recurrence rates were 16.7% and 12.7% for melasma and solar lentigo, respectively. Postinflammatory hyperpigmentation developed in 1 patient, but no serious side effects were noted. CONCLUSION: Low-fluence QSNYL is effective in treating melasma and small type solar lentigo in Asians. The authors' study also demonstrated that lesion thickness, vascularity, and mast cell activity can be used to predict the efficacy of the treatment of these lesions.

Postinflammatory hyperpigmentation associated with treatment of solar lentigines using a Q-Switched 532-nm Nd: YAG laser: a multicenter survey.

PURPOSE: To characterize the risk factors of Korean patients for postinflammatory hyperpigmentation (PIH) during treatment of solar lentigines using a Q-switched 532-nm Nd: YAG (QS 532 NY) laser. MATERIALS AND METHODS: The present retrospective multicenter study was conducted at the dermatology clinics of five tertiary hospitals in Korea. Between October 2007 and January 2013, 516 patients were enrolled and reviewed for clinical features and factors associated with PIH. RESULTS: The overall incidence of PIH was 20.3%. We demonstrated that patients with erythematous lentigines presented with PIH more frequently compared with those without erythematous lentigines. Among several coexisting conditions, facial diffuse dyschromia was significantly associated with PIH. Furthermore, PIH occurred more frequently in patients with invisible pores and velvety skin. However, age, sex, Fitzpatrick skin's phototype and season of treatment showed little association with PIH. CONCLUSIONS: When a QS 532 NY laser is used to treat individuals with erythematous lentigines, invisible pores and velvety skin, and facial diffuse dyschromia, clinicians should be cautious and consider preventive measures.

Q-Switched 660-nm Versus 532-nm Nd: YAG Laser for the Treatment for Facial Lentigines in Asian Patients: A Prospective, Randomized, Double-Blinded, Split-Face Comparison Pilot Study.

BACKGROUND: Q-switched (QS) 532-nm lasers are widely used to treat solar lentigines. OBJECTIVE: To compare the efficacy and safety of 660-nm and 532-nm QS neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers in the treatment for lentigines in Asians. MATERIALS AND METHODS: The halves of each face (randomly chosen) of 8 Korean Fitzpatrick Skin Type III-IV women with facial solar lentigines were treated with either 660-nm or 532-nm lasers. Pigmentation was measured objectively using a profilometric skin analysis tool and subjectively using the pigmentation area and severity index (PSI) score, global assessment of the aesthetic improvement scale (GAIS), and a patient satisfaction score at Weeks 4 and 8. RESULTS: Seven patients completed the study. No significant differences were found in the PSI, GAIS, patient satisfaction score, and melanin average score between the lasers. The melanin average level was significantly reduced by the 660-nm laser but not the 532-nm laser at Week 8 compared with the baseline. CONCLUSION: Both 660-nm and 532-nm QS Nd:YAG lasers effectively reduce pigmentation for up to 8 weeks with high patient satisfaction. The new 660-nm laser therefore increases the treatment options for lentigines in Asian skin.

Low-fluence Q-switched 1,064-nm neodymium-doped yttrium aluminum garnet laser for the treatment of facial partial unilateral lentiginosis in Koreans.

BACKGROUND: Established pigment lasers have been used in partial unilateral lentiginosis (PUL) have shown unsatisfactory results. OBJECTIVE: To determine the effectiveness and safety of low-fluence 1,064-nm Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser treatment of PUL in Koreans. MATERIALS AND METHODS: Ten Korean patients with facial PUL were treated with 1,064-nm QS Nd:YAG laser, 7-mm spot size, 1.5- to 2.5-J/cm(2) fluence at 2-week intervals. Standard digital photographs were taken under the same condition at baseline and at each follow-up visit. Independent dermatologists evaluated the photographs. All patients completed a questionnaire to assess their subjective satisfaction with the laser treatment using a 5-point grading system. Degree of pain was assessed using a visual analog scale (0-10). Any complications and side effects were recorded at each visit. Patients were followed up every 4 weeks for 12 weeks after the last laser treatment. RESULTS: Five of 10 patients (50%) had achieved excellent improvement (76-100%) at the end of treatment, and the remaining 50% had good improvement (51-75%). In patient self-evaluation of the degree of improvement of PUL, nine (90%) assessed it as very much to much improved (>50% improvement), and 1 (10%) assessed it as moderate (50-75%). Subjects rated the pain associated with laser treatment at a mean score of 3.3 (range: 1-5) on a scale of 1 to 10. Mottled hypopigmentation developed in two patients. At follow-up, 12 weeks after the last laser session, all of the patients had partial recurrence, which wqw resolved with one to two sessions of laser treatment. CONCLUSION: Low-fluence 1,064-nm QS Nd:YAG laser treatment for facial PUL in Koreans showed improvement with no significant side effects. We recommend the low-fluence 1,064-nm QS Nd:YAG laser as a treatment option for facial PUL.

Effect of spot size and fluence on Q-switched alexandrite laser treatment for pigmentation in Asians: a randomized, double-blinded, split-face comparative trial.

BACKGROUND: Q-switched laser treatment for pigment disorders commonly leads to postinflammatory hyperpigmentation (PIH) in Asians. OBJECTIVES: To evaluate the effect of spot size and fluence on Q-switched alexandrite laser (QSAL) treatment for pigmentation in Asians. METHODS: Ten patients with freckles, 18 with lentigines, and 8 with acquired bilateral nevus of Ota-like macules (ABNOM) received 1 session of QSAL treatment for a 3-mm spot on one cheek and a 4-mm spot on the other cheek. The lowest fluences to achieve a visible biologic effect were chosen. RESULTS: The patients with freckles experienced the highest improvement rate (83-84%), followed by those with lentigines (52%) and ABNOM (35%). Similar efficacy was observed for both cheeks (p > 0.05). PIH developed in 10% (1/10), 44% (8/18), and 75% (6/8) of the patients with freckles, lentigines, and ABNOM, respectively. The severity of PIH was lower in the 4-mm spot with a lower fluence than in the 3-mm spot with a higher fluence in patients with lentigines (p = 0.03), but not in those with freckles or ABNOM. CONCLUSIONS: Using a larger spot to achieve the same biologic effect at a lower fluence is associated with equal efficacy and less-severe PIH in patients with lentigines.

Laser treatment of dark skin: an updated review.

The growing diversification of the patient population coupled with the increasing demand for cosmetic laser rejuvenation has highlighted the need to develop cutaneous laser systems and establish treatment protocols for patients with a wide range of skin conditions and phototypes. Recent technologic advancements have provided viable treatment options to achieve clinical outcomes that were previously only attainable in patients with lighter skin tones. This review provides an updated discussion of the range of laser treatments available for pigmented skin and sets the stage for further advancements. Pigment-specific laser technology with green, red, or near-infrared light targets a variety of pigmented lesions such as lentigines, ephelides, café-au-lait macules, and melanocytic nevi as well as tattoos and unwanted hair. Short-pulsed alexandrite, ruby, and neodymium:yttrium-aluminum-garnet (Nd:YAG) lasers are used for pigmented lesions and tattoos, whereas their longer pulse-width laser counterparts are used for laser-assisted hair removal. Vascular lesions and hypertrophic scars can be treated with a variety of vascular-specific lasers, but it is the pulsed dye laser (PDL) that has long been the gold standard treatment for these lesions due to its high specificity for hemoglobin and its ability to improve skin surface texture in children and adults. Laser skin resurfacing techniques for photodamaged skin and atrophic scars have been optimized with fractional technology to produce excellent clinical outcomes and minimal complication risks. Radiofrequency and nonablative lasers are also used to provide skin tightening and collagen remodeling with virtually no postoperative recovery.

In vivo microscopic approaches for facial melanocytic lesions after quality-switched ruby laser therapy: time-sequential imaging of melanin and melanocytes of solar lentigo in Asian skin.

BACKGROUND: The quality-switched ruby laser (QSRL) has been widely used for the treatment of pigmented lesions, but clinical evaluations in most studies have been conducted on macroscopic skin color observation comparing the laser-treated skin with its nontreated surrounding area. A few investigations examined skin changes after laser therapy at a cellular level, but almost none did so noninvasively. OBJECTIVE: To elucidate the dynamic changes after QSRL irradiation of facial solar lentigo using noninvasive optical techniques. MATERIALS AND METHODS: Time-sequential imaging of Japanese female patients with a clinical diagnosis of solar lentigo was performed using ultraviolet photography, high-magnification videomicroscopy, and reflectance-mode confocal microscopy to examine pigmentary change after QSRL irradiation. RESULTS: The present study showed that remaining melanocytes were visible in the solar lentigo of all subjects when crusts peeled off, despite hardly observable skin pigmentation to the naked eye. Moreover, noninvasive confocal imaging revealed that pigmented melanocytes varied in each solar lentigo after QSRL treatment, as indicated by melanin reflection level. CONCLUSIONS: Optical techniques facilitate the evaluation of the in vivo dynamics of epidermal-melanocytic changes in solar lentigo after QSRL therapy and may be useful for monitoring outcomes after laser irradiation.

Q-switched alexandrite laser treatment of oral labial lentigines in Chinese subjects with Peutz-Jeghers syndrome.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is characterized by gastrointestinal hamartomatous polyps and visible mucocutaneous lentigines distributed in the oral and anal mucosa, hands, face, and nails. Although there are many reports regarding successful treatment of intestinal polyps of PJS, there is little information regarding treatment of lentigines. Q-switched lasers are the preferred method of treatment for benign melanocytic lesions. OBJECTIVE: To evaluate the efficacy of the Q-switched alexandrite laser (QSAL) in treating oral labial lentigines of PJS. METHODS AND MATERIALS: Fourteen cases of laser treatment of oral labial lentigines in patients diagnosed with PJS were studied between 2005 and 2008. All were treated using a single treatment with a QSAL with a 3-mm handpiece and a fluence of 4.0 to 9.0 J/cm(2). Retrospective analysis of the effect of QSAL was conducted. RESULTS: All 14 cases exhibited successful elimination of treated lentigines after one laser treatment. There were significant acute side effects. After a median 2-year follow-up, there were no recurrences or scars in treated sites. CONCLUSIONS: The QSAL provides effective treatment for removal of labial lentigines associated with PJS.

A pulsed dye laser with a 10-mm beam diameter and a pigmented lesion window for purpura-free photorejuvenation.

BACKGROUND AND OBJECTIVES: In traditional pulsed dye lasers (PDLs), power limitations and pulse characteristics have compromised purpura-free procedures. This study evaluated a new PDL with a modified pulse structure and a 10-mm beam diameter for purpura-free photorejuvenation. A compression handpiece was used for targeting lentigines. MATERIALS AND METHODS: Twenty patients with skin types I to III were treated three times at 3- to 4-week intervals. The first pass was delivered through a 10-mm compression handpiece to target pigment dyschromias using fluences between 6.5 and 8.0 J/cm(2) with a 1.5-ms pulse duration. A second pass was then performed with a 10-mm spot with fluences between 9.5 and 10 J/cm(2), a 20-ms pulse duration, and cryogen spray enabled. Improvement was evaluated by comparing pre- and posttreatment photographs and live subjects 1 month after the third treatment. RESULTS: In the majority of patients, >90% reduction of fine telangiectasias (<0.6 mm) and dark lentigines was achieved. Pigmented dyschromias improved proportional to the degree of pigment at presentation. Avoidance of purpura with the compression handpiece was dependent on obtaining proper compression before laser emission. Mean textural improvement was 34%. CONCLUSIONS: The new 595-nm PDL is highly effective for two-pass purpura-free improvement of telangiectases, pigment dyschromias, and texture.

Case reports: clearance of lentigines in Japanese men with the long-pulsed alexandrite laser.

Benign pigmented lesions can be effectively treated with multiple modalities including lasers. The treatment of pigmented lesions in phototype IV skin is more complicated and challenging given the risk of pigmentation changes and scarring. We present the novel use of the long-pulsed Alexandrite 755 nm laser for the treatment of solar lentigines in sun-reactive phototype IV skin of patients of Japanese decent. Our Japanese patients cleared with one treatment with no pigmentary changes or scarring. No recurrences were noted to date. The long-pulsed Alexandrite 755-nm laser is a novel, safe, and effective treatment of solar lentigines in Japanese patients.