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BACKGROUND Enlarged facial pores are one of the common skin signs of photoaging that patients seek treatment for. However, objective data and long-term assessment on the efficacy and safety of therapeutic procedures for this condition are limited. OBJECTIVE To objectively evaluate the efficacy and safety of a 1064-nm picosecond laser with microlens array (MLA) for pore tightening. METHODS Twenty-five patients with enlarged pores received three treatments with a 1064-nm picosecond laser coupled with MLA at 4-week intervals. Patients were evaluated using objective (measurement of pore volume using three-dimensional photography) and subjective (clinical evaluation by two blinded dermatologists) assessments at baseline and at the 1-, 3-, and 6-month follow-ups. Adverse effects were also recorded during each visit. RESULTS After three treatments, there was a significant reduction of pore size from baseline (p

BACKGROUND AND OBJECTIVE: The long-term efficacy of a picosecond alexandrite laser (PSAL) with a diffractive lens array (DLA) for the treatment of photoaging is absent. To observe the long-term efficacy of PSAL for the treatment of photoaging. STUDY DESIGN/MATERIALS AND METHODS: Each patient (n = 10) received 10 treatments at 2-week intervals. One side of the face was randomly selected for treatment. At 1, 3, 6, and 36 months after the final treatment, two blinded physicians evaluated photographs with four clinical indicators of photoaging (dyschromia, skin texture, skin laxity, and rhytids). A quartile scale was used. RESULTS: At baseline, there were no significant differences in dyschromia, skin texture, facial laxity, or rhytids between the treated and control sides (P > 0.05). Picosecond laser-treated side showed 0.85 and 1.05 (both P < 0.05) better for dyschromia at 3- and 6-month follow-up, and 0.6 (P < 0.05) better for skin texture at 6-month follow-up. At 36-month follow-up, the degree of photoaging is intensified on the control side while the rejuvenation efficacy maintained on the treated side, with 1.4, 0.75, and 0.8 (all P < 0.05) better for dyschromia, skin texture, and rhytids relative to the control side measures. CONCLUSION: Our results demonstrate the long-term efficacy and safety of PSAL with DLA for the treatment of facial photoaging. LIMITATION: Small sample size and the lack of objective evaluation. Lasers Surg. Med. © 2021 Wiley Periodicals LLC.

Background and objectives In this study, the threshold fluences for disrupting the melanosomes for pigmented skin lesion treatment were determined using a 755-nm picosecond laser for clinical use. Based on the melanosome disruption thresholds, incident fluences corresponding to the target lesion depths were evaluated in silico for different laser spot sizes. Study design/materials and methods Melanosome samples were isolated from porcine eyes as alternative samples for human cutaneous melanosomes. The isolated melanosomes were exposed to 755-nm picosecond laser pulses to measure the mean particle sizes by dynamic light scattering and confirm their disruption by scanning electron microscopy. The threshold fluences were statistically determined from the relationships between the irradiated fluences and the mean particle sizes. Incident fluences of picosecond laser pulses for the disruption of melanosomes located at different depths in skin tissue were calculated through a light transport simulation using the obtained thresholds. Results The threshold fluences of 550- and 750-picosecond laser pulses were determined to be 2.19 and 2.49 J/cm2 , respectively. The numerical simulation indicated that appropriate incident fluences of picosecond laser pulses differ depending on the depth distribution of the melanosomes in the skin tissue, and large spot sizes are desirable for disrupting the melanosomes more deeply located within the skin tissue. Conclusion The threshold fluences of picosecond laser pulses for melanosome disruption were determined. The incident fluence analysis based on the thresholds for melanosome disruption provides valuable information for the selection of irradiation endpoints for picosecond laser treatment of pigmented skin lesions. Lasers Surg. Med. © 2021 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals LLC.

Background and objectives Scalp micropigmentation (SMP) is a useful technique that applies permanent camouflage for hair loss and scarring. However, suboptimal outcomes necessitate removal. To date, there have been no reports of SMP removal with a picosecond laser. In this report, we demonstrate the safety and efficacy of 1064 nm picosecond neodymium yttrium aluminum garnet (Nd:YAG) laser for the removal of SMP. Study design/materials and methods This was a case series of four patients who presented with undesirable SMP. Following induction of adequate cutaneous anesthesia, a 1064 nm picosecond Nd:YAG laser was applied to all surface areas with SMP. Post-operative care consisted of 1% dimethicone ointment applied twice daily to the affected areas for 3-7 days. Patients were evaluated after 3-4 weeks and additional treatment sessions were undertaken if necessary. Results Clearance of SMP was achieved within 1-3 treatment sessions in all cases. There were no unexpected adverse events. Conclusion Picosecond Nd:YAG laser is an excellent treatment option for undesirable SMP. It is safe and effective and typically requires fewer treatment sessions than traditional tattoo removal. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Background and objectives To investigate the safety and efficacy of a dual-wavelength 1064/532-nm picosecond-domain laser for tattoo removal in Vietnamese patients. Study design/materials and methods This prospective clinical study enrolled 30 subjects with 52 decorative tattoos treated with up to six treatments of laser removal at intervals of 6-8 weeks. Safety and efficacy were assessed at each treatment session and at 4 weeks after the final session. A "good" response was defined as at least 75% clearance of tattoo pigments. Results A significant reduction of tattoo appearance was achieved in all subjects. 88.5% of tattoos exhibited a "good" response to treatment by the end of the six sessions and more than 36% of tattoos exhibited better than "good" responses. Adverse events were common in the early period after treatment but did not persist in most patients. Only one case of prolonged hypopigmentation was reported. Conclusions Treatment using a 1064/532-nm picosecond laser is an effective approach for removal of decorative tattoos, which poses a minimal risk of long-term adverse events in patients with Fitzpatrick skin type III or IV. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Background and objective Until recently, quality-switched nanosecond lasers have been the workhorse lasers in treating pigmented lesions. However, the recently commercialized picosecond lasers have provided physicians with a novel method to manage pigmented lesions. Most recently, the first picosecond laser with a 730-nm wavelength was developed to specifically target melanin and melanocytes. Study design/materials and methods We report on two Asian patients with freckles, lentigines, and melasma who were successfully treated with a novel 730-nm Ti:Sapphire picosecond laser (Picoway®; Syneron Candela, Corp). The clinical outcome was measured by the global percent of clearance, which was evaluated by blinded observers by comparing the post-treatment photographs with the baseline photographs. Results In both patients, a significant pigmentary reduction was achieved with only one treatment session. In both patients, the treatments were well tolerated with minimal discomfort even without topical anesthesia. No post-inflammatory hyperpigmentation or repigmentation was observed until the 6-week follow-up. The pigmentary conditions treated included freckles, lentigines, and melasma. Both subjects showed clinical improvement, with the best results observed for the treatment of freckles such that 95% of the lesions achieved excellent response (75-94% lightening). Conclusion The results of this case report indicate that a novel 730-nm Ti:Sapphire picosecond laser may be effective and safe in treating pigmentary disorders in darker-skinned patients. Therefore, further well-designed, prospective clinical trials are warranted to establish the potential of 730-nm picosecond lasers and determine the optimal treatment parameters in comparison to existing laser and light modalities. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Background and objectives The use of picosecond laser in dermatology was originally focused on optimizing the removal of unwanted tattoos. Subsequent advances in this technology have broadened its clinical indications to include treatment of benign pigmented lesions, photodamage, melasma, and scar revision. In this systematic review, evidence-based recommendations are developed for the use of picosecond laser in dermatology. Study design/materials and methods A comprehensive search of the English language literature was performed up to and including November 2019. Relevant citations were individually evaluated, synthesized, and categorized based on the Level of Evidence. With the addition of the authors' combined clinical experience, clinical recommendations were developed. Results After application of inclusion and exclusion criteria, a total of 77 unique studies were evaluated. Treatment of benign pigmented lesions was associated with level I-IV evidence; rejuvenation was associated with level II evidence; melasma was associated with level II evidence; scar revision was associated with level II-III evidence; tattoo removal was associated with level I evidence. Conclusion Picosecond laser is a safe and effective treatment modality for an increasing range of dermatologic indications. Further development of this technology is warranted. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.

BACKGROUND AND OBJECTIVES The picosecond (PICO) laser has been a new and promising device. But, so far, there have not been many prospective studies investigating the efficacy in acne scar treatment. This study evaluated the efficacy and safety of the dual-wavelength picosecond laser in the treatment of acne scar. STUDY DESIGN/MATERIALS AND METHODS A total of 20 patients with skin type III-IV were enrolled in this study. Eighteen patients completed the study. All patients completed six treatment sessions within a 1-month interval. All patients were treated using both 532 and 1,064 nm fractionated dual-wavelength picosecond handpieces. In evaluation, Goodman and Baron's quantitative global acne scarring grading system (GSS) was scored by two physicians. Patients also judged the results themselves by Visual Analog Scale (VAS) and pain score. RESULTS The average baseline score of GSS quantity and quality were 15.22 and 3.00, respectively. The final scores were 10.61 and 2.33. The average baseline of patient VAS score was 4.28. The final score was 2.00. All scores achieved statistical significance (P

Background and objectives Q-switched (QS) and picosecond lasers can effectively and safely remove unwanted tattoo pigments. Cosmetic mucosal tattoos are rare and there are only a handful of cases of successful laser tattoo removal, all with QS 1064-nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. Study design/materials and methods A 19-year-old Fitzpatrick skin-type II female presented for treatment of a 6-month-old, black tattoo on the mucosal surface of her lower lip. She underwent six treatment sessions with a QS 694-nm ruby laser on months 0, 1, 3, 5, 7, and 12. A 30-year-old Fitzpatrick skin-type IV male presented for treatment of a 10-year-old black tattoo on his left buccal mucosa. He underwent one treatment with 755-nm alexandrite picosecond lasers. Results One month after last treatment, both patients demonstrated marked improvement to the treatment area without scarring or dyspigmentation. Conclusions Given the excellent results seen in the patients presented here, the authors recommend that lasers should be the first-line treatment for the removal of unwanted cosmetic mucosal tattoos, which are typically easier to remove than cutaneous tattoos and can be accomplished with various wavelengths in the picosecond and nanosecond domains. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Objectives Quality-switched (QS) lasers are known to be an effective treatment for removing solar lentigines, however, high incidence of post-inflammatory hyperpigmentation (PIH) is a concern in darker skin types. The objective of this study was to evaluate the efficacy and safety of a dual-wavelength and dual-pulse width picosecond Nd:YAG laser for removing solar lentigines in Asians. Methods This was a prospective, IRB-approved study. Twenty cases with solar lentigines on the face were enrolled for treatment and evaluated at 1- and 3-month after the final treatment. Results were assessed by blinded evaluators using a 5-grade percentage improvement scale and Melanin index (MI) measured by a reflectance spectrophotometer. A patient self-assessment questionnaire was also administered using a 5-grade improvement scale. Additional treatment was performed if the improvement was less than 75% or the lentigo partially remained after 4 weeks. Histological evaluation was performed to compare the differences between the current picosecond laser and a QS Nd:YAG laser 532-nm using light and electron microscopy. Results Forty-three lesions in 20 females, skin type III or IV, age 53.7 ± 9.75 were treated and evaluated. The laser setting was: 532-nm, 750 picoseconds, average fluence of 0.35 ± 0.06 J/cm [2] using a spot size of 3 or 4 mm. Forty lesions (93.02%) achieved over 75% clearance with a single treatment and the other three lesions (6.98%) needed two treatments. PIH occurred only in 4.65% of lesions. The average score of the blinded evaluators' assessment was 4.77 and 4.58 on a 5-grade percentage improvement scale. The patients' self-assessment rating was 4.76 and 4.67 on a 5-grade scale at 1- and 3-month follow-up, respectively. The improvement rate of relative MI (MI in the lesion minus that of the normal area) was 77.60 ± 36.27% and 76.93 ± 20.95% at 1-and 3-month follow-up. Histology showed vacuolar formation by both lasers in the epidermis that were different sizes between lasers. Electron microscopy showed destruction of melanosomes with surrounding tissue damage with the QS laser and without particular damage with the picosecond laser. Conclusions To the best of our knowledge, this is the first study using a picosecond Nd:YAG laser 532-nm for removing solar lentigines in darker skin types that includes histological evaluation. Although there are many options to treat solar lentigines, our results suggest that picosecond laser with preferable endpoint determination can be a safer and more effective treatment over conventional treatments in Asian patients. Lasers Surg. Med. 50:851-858, 2018. © 2018 Wiley Periodicals, Inc.

Objective The picosecond 755 nm alexandrite laser using a diffractive lens array has demonstrated consistent clinical efficacy for improving the appearance of acne scarring and wrinkles amongst other benefits. This small pilot study is to assess the difference, if any, in clinical benefit if a higher than the standard protocol for number of pulses delivered to a tissue area is used compared to the standard protocol guidelines. Method Seven subjects received treatment to one side of the face with a standard protocol number of laser pulses with the other side of the face receiving higher than standard number of pulses from the same 755 nm picosecond laser using an additional diffractive lens array. Photographs at final follow up were compared to baseline by two blinded Board Certified Dermatologists and assessed for improvements to acne scarring using a 6-point grading score, for wrinkles using the Fitzpatrick Wrinkle & Elastosis 3-point grading scale and a Global Aesthetic Improvement Scale assessment. Subjects also completed a satisfaction questionnaire. Results For the acne scarring subjects, the average improvement from baseline to final follow up was 4.0 +/- 1.0 for the standard treated side and 4.5 +/- 0.5 for the high pulse side. There was no statistically significant difference between the two treated sides (P > 0.05, n = 3 paired t-test). For the wrinkle subjects, the average grading of the standard pulse side improved from 2.0 +/- 0.82 to 1.75 +/- 1.0 from baseline to final follow-up. The high pulse side improved from 1.5 +/- 1.0 to 1.125 +/- 0.25 from baseline to final follow-up. There was no statistically significant difference between the improvement of the standard and high pulse treatment sides (P > 0.05, n = 4 paired t-test). The comparison of baseline to final follow-up images of each subject found both sides to be Much or Very Much improved with no statistically significant difference between the standard and high pulse sides (P > 0.05, n = 7 paired t-test). Six of the seven subjects did not note any difference between the effect on different sides of the face and four of the seven rated their overall improvement after treatment as Good, three subjects as Reasonable and one subject with Slight Improvement. All subjects found the treatment comfortable and easy to tolerate and there was no increased incidence of side effects other than the mild occurrences typically observed for this type of treatment. Conclusion This is a small pilot study with limited subject numbers and further data is needed to be able to make firm conclusions of observed trends, which suggest that the use of higher than standard suggested protocol number of pulses with the diffractive lens array and the 755 nm picosecond laser does not appear to offer any additional benefit over that that can already be achieved with the standard number of pulses, but also does not increase risk of detrimental post treatment effects either. Lasers Surg. Med. 50:51-55, 2018. © 2017 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Background and objectives This study was performed to better understand the cutaneous effects of using a fractional picosecond laser at 755 nm with a diffractive lens array and a picosecond Nd:YAG laser at 532 mn and 1064 nm with a holographic optic. We characterized the injuries created by these devices on skin clinically and histologically over 24 hours. With this information we modeled the effects of these devices on a cutaneous target. Methods Eight patients, representing Fitzpatrick skin types I-VI, were treated on their backs with a picosecond Alexandrite laser with a diffractive lens array, as well as a picosecond Nd:YAG laser at 532 nm and 1064 nm with a holographic optic. Photographs were taken 15 minutes and 24 hours after treatments. Punch biopsies were obtained at 24 hours and examined histologically. Results Treatment with the picosecond Nd:YAG laser at both 532 nm and 1064 nm with the holographic optic revealed erythema and small scatted areas of petechial hemorrhage areas immediately and in many cases at 24 hours after treatment. The 755 nm picosecond Alexandrite laser with diffractive lens array produced erythema immediately after treatment, which largely dissipated 24 hours later. Histologies revealed intra-epidermal vacuoles with all three wavelengths. Fractional picosecond Nd:YAG laser at 532 nm and 1064 nm with the holographic optic showed focal areas of dermal and intra-epidermal hemorrhage with areas of vascular damage in some patients. Conclusions This study demonstrates that both fractional picosecond devices produce vacuoles in the skin, which are most likely due to areas of laser induced optical breakdown (LIOB). In the patients (skin type II-IV) we observed scatter areas of hemorrhage in the skin, due to vascular damage with the 532 nm and 1064 nm, but not with 755 nm wavelengths. Lasers Surg. Med. 50:37-44, 2018. © 2017 Wiley Periodicals, Inc.

Background and Objectives Melasma is a common acquired, chronic hypermelanosis and still remains a therapeutic challenge. The low-fluence 1 064 nm Q-switched Nd:YAG laser is the most widely used for the treatment of moderate to severe melasma in Asia. Recently, the picosecond laser has been introduced for various pigmentary disorders such as melasma. We evaluated the efficacy and safety of a picosecond laser with dual-wavelengths (1 064 and 595 nm) and topical 2% hydroquinone (HQ) combination therapy on patients with melasma, and compared results with those obtained with 2% HQ alone. Study Design/Materials and Methods This was a prospective, randomized, split-face, controlled trial comparing two treatments with combined 7 week 2% HQ (daily) and 5 week picosecond laser (weekly) versus 7 week 2% HQ. The primary efficacy variable was the change rate of the relative lightness values (RL*I) at week 7 from baseline. RL*I at a follow-up visit, modified melasma severity score (mMASI), and satisfaction were assessed. Results Picosecond laser and 2% HQ had superior efficacy to 2% HQ alone: 30/39 (76.92%) subjects on combination treatment achieved ≥51% improvement of RL*I versus 1/39 (2.56%) subjects on 2% HQ. The mMASI, RL*I, and satisfaction on the laser-treated side at week 7 supported these results. Aside from RL*I, no difference between the laser-treated versus control side was found after follow-up. No serious adverse events were reported. Conclusion A 750 picosecond laser using 1 064 and 595 nm was effective and safe for the treatment of Korean melasma patients. The picosecond laser with dual-wavelength used in this study can reduce the photothermal effect generated during the removal of pigment and total duration of the procedure, and can be expected to reduce the occurrence of adverse events. Lasers Surg. Med. © 2017 Wiley Periodicals, Inc.

Author(s): Balu, Mihaela; Lentsch, Griffin; Korta, Dorota Z; Konig, Karsten; Kelly, Kristen M; Tromberg, Bruce J; Zachary, Christopher B | Abstract: ImportanceImprovements in skin appearance resulting from treatment with fractionated picosecond-lasers have been noted, but optimizing the treatment efficacy depends on a thorough understanding of the specific skin response. The development of non-invasive laser imaging techniques in conjunction with laser therapy can potentially provide feedback for guidance and optimizing clinical outcome.ObjectiveThe purpose of this study was to demonstrate the capability of multiphoton microscopy (MPM), a high-resolution, label-free imaging technique, to characterize in vivo the skin response to a fractionated non-ablative picosecond-laser treatment.Design, setting, and participantsTwo areas on the arm of a volunteer were treated with a fractionated picosecond laser at the Dermatology Clinic, UC Irvine. The skin response to treatment was imaged in vivo with a clinical MPM-based tomograph at 3 hours and 24 hours after treatment and seven additional time points over a 4-week period.Main outcomes and measuresMPM revealed micro-injuries present in the epidermis. Pigmented cells were particularly damaged in the process, suggesting that melanin is likely the main absorber for laser induced optical breakdown.ResultsDamaged individual cells were distinguished as early as 3 hours post pico-laser treatment with the 532 nm wavelength, and 24 hours post-treatment with both 532 and 1064 nm wavelengths. At later time points, clusters of cellular necrotic debris were imaged across the treated epidermis. After 24 hours of treatment, inflammatory cells were imaged in the proximity of epidermal micro-injuries. The epidermal injuries were exfoliated over a 4-week period.Conclusions and relevanceThis observational and descriptive pilot study demonstrates that in vivo MPM imaging can be used non-invasively to provide label-free contrast for describing changes in human skin following a fractionated non-ablative laser treatment. The results presented in this study represent the groundwork for future longitudinal investigations on an expanded number of subjects to understand the response to treatment in different skin types with different laser parameters, critical factors in optimizing treatment outcome. Lasers Surg. Med. 49:555-562, 2017. © 2017 Wiley Periodicals, Inc.

Background Conventional tattoo removal consists of single-pass treatments, spaced 7-8 weeks apart, for a total of 7-10 sessions. A major limiting factor of this procedure is the development of cavitation bubbles and vacuoles within the epidermis and dermis that result from the rapid heating of tattoo particles by the laser. While multiple-pass methods using the R20 protocol or the PFD patch enhance tattoo removal through epidermal clearance, they have no effect on deep-intradermal pigment associated vacuoles that arise from treatment with lasers such as the Q-switched laser. Methods A 28-year-old female with Fitzpatrick skin Type V presented for treatment of a 6-year-old professional black tattoo on the left ventral wrist. She underwent three treatment sessions at 6-8 week intervals using a commercial 1,064-nm picosecond Nd:YAG laser (PicoWay; Candela, Wayland, MA) and a perfluorodecalin (PFD) patch (Merz; Raleigh, NC). At each treatment session, she received two passes with 1,064-nm, 4-mm spot size, a fluence ranging from 2.8 to 3.2 J/cm2 and a laser repetition rate of 2 Hz. Between laser passes and following the final laser pass, the medial portion of the tattoo was treated with acoustic shock wave therapy (ASWT) using the Zwave device (Zimmer Medizin Systems; Irvine, CA) with 90 mJ, 22 Hz, and 1,200 pulses. Results After three treatment sessions, there was 80% clearance of the medial portion of the tattoo that received the ASWT compared with 60% clearance of the lateral portion of the tattoo that was treated with the picosecond 1,064-nm Nd:YAG laser and PFD patch alone. In the days following each treatment session, the patient noted consistently less edema, erythema and epidermal crusting on the portion of the tattoo that received the ASWT. Conclusion We report a case of 80% tattoo clearance with ASWT in a patient with Fitzpatrick type V skin compared with 60% clearance with the picosecond 1064-nm Nd:YAG laser and PFD patch alone. The concurrent use of the PFD patch, which facilitated multi-pass treatments, may have also increased tattoo fading in this patient. ASWT may enhance tattoo clearance by increasing lymphatic drainage and increasing metabolic activity in the treated area, thereby accelerating the clearance of dermal pigment vacuoles produced by the picosecond laser and minimizing epidermal side effects such as erythema, edema, and crusting. Lasers Surg. Med. 50:890-892, 2018. © 2018 Wiley Periodicals, Inc.

Introduction Picosecond lasers have been reported to be effective for removal of tattoo pigment. This prospective study evaluated the efficacy and safety of the treatment of peri-oral and -ocular wrinkles using a novel diffractive lens array coupled with a picosecond 755 nm alexandrite laser. Methods Forty female subjects presenting with wrinkles from photodamage were enrolled in an IRB approved study. Subjects received four picosecond diffractive lens array treatments to the full face at 1 month intervals. Six subjects were biopsied (two subjects at 1 month, two subjects at 3 months, and two subjects at 6 months). Digital photographic images were taken at 1, 3, and 6 months post-final treatment visits. Images were graded by blinded physicians for fine lines/wrinkles, erythema, dyschromia, and global improvement. Data on discomfort level, satisfaction, and side effects were recorded. Results Overall blinded physician rated global improvement ranged from improved to much improved at 1-, 3-, and 6-month time points. At baseline the average Fitzpatrick wrinkle score was 5.48. At the 6-month follow-up the average score was 3.47. The overall average change in score from pre-treatment to post-treatment was 1.97. Subject self-assessment at 6 months indicated that 90% of subjects were extremely or satisfied with their results. Unanticipated adverse events were absent with anticipated post-treatment erythema lasting for just several hours. Conclusions A novel diffractive lens array used with a picosecond 755 nm alexandrite laser for treatment of wrinkles is highly effective and safe for wrinkles and other signs of photoaging. Lasers Surg. Med. © 2016 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Studies using a 755 nm picosecond laser with a focus lens array have been reported to be effective for facial wrinkles and pigmentation. This study reports the safety and efficacy using a shorter interval of 2-3 weeks between treatments. Nineteen female subjects and one male subject, primarily Fitzpatrick skin types II and III (one skin type I), who had mild to moderate wrinkles and sun-induced pigmentation were enrolled and treated using the 755 nm PicoSure Laser with focus lens array. The skin was cleansed then wiped with an alcohol wipe prior to treatment. Lidocaine 30% ointment and/or forced air cooling could be used to increase subject comfort. Adjacent pulses, with minimal overlap (10% or less), were delivered to the full face. Subjects received four treatments, performed at 2-3-week intervals. The laser energy used was 0.71 J/cm2 . The physician administered 3-7 passes with an average total of 6,253 pulses per treatment. Follow-up visits occurred at 1 and 3 months post-last treatment at which the physician scored satisfaction and improvement and subjects scored satisfaction and likelihood to recommend to others. The most common side effects were mild swelling, pain, redness, and crusting, most of which subsided within hours of the treatment, with the latest resolving within 48 hours. This is similar to a previous reported study (Weiss et al. ASLMS 2015) where treatments were performed every 6 weeks with side effects resolving within 24 hours. At the 1 and 3 month follow-up visits, 94% (n = 19) and 93% (n = 15) of subjects scored themselves as satisfied or extremely satisfied with their overall results and 81% and 93% were likely to recommend the treatment based on global assessment, respectively. The treating physician was satisfied with 93% of subject's overall results. Three blinded evaluators were able to correctly identify the baseline from post-treatment photographs in 77% of the subjects at the 1 month follow-up and 69% of the subjects at the 3 month follow-up, on average. The average treatment pain score was 4.2 on a 1-10 scale. A compressed treatment interval expedites results without increasing side effects and resulted in a high physician and subject satisfaction rate. Lasers Surg. Med. 48:723-726, 2016. © 2016 Wiley Periodicals, Inc.

Background and Objectives Although technology and tattoo removal methods continue to evolve, yellow pigment clearance continues to be challenging and usually unsuccessful. We describe a case series of six tattoos containing yellow ink, successfully treated with a frequency-doubled Nd:YAG 532-nm picosecond laser. Study Design/Materials and Methods Case series with six subjects participating for the treatment of multicolored tattoos that contain yellow pigment. Treatments performed with a frequency-doubled Nd:YAG 532-nm picosecond laser at 6–8 week intervals. Results One subject achieved complete clearance of the treated site after one session, and five subjects required 2–4 treatments to achieve over 75% clearance. Minimal downtime was experienced, and no scarring or textural skin changes were observed in any of the treated sites. Conclusions This is the first case series that demonstrates effective and consistent reduction of yellow tattoo ink using a frequency doubled Nd:YAG 532-nm laser with a picosecond pulse duration. Treatments were well tolerated and subjects had positive outcomes. This is a small observational case series from an ongoing clinical trial, and studies with a larger sample size and comparative group are needed in the future. in vivo. Lasers Surg. Med. 47:285–288, 2015. © 2015 Wiley Periodicals, Inc.

Background Laser techniques have been introduced into dentistry to overcome the drawbacks of traditional treatment methods. The existing methods in dental clinical operations for tooth crown preparation have several drawbacks which affect the long-term success of the dental treatment. Objective To develop an improved robotic system to manipulate the laser beam to achieve safe and accurate three-dimensional (3D) tooth ablation, and thus to realize automatic tooth crown preparation in clinical operations. Method We present an automatic laser ablation system for tooth crown preparation in dental restorative operations. The system, combining robotics and laser technology, is developed to control the laser focus in three-dimensional motion aiming for high speed and accuracy crown preparation. The system consists of an end-effector, a real-time monitor and a tooth fixture. A layer-by-layer ablation method is developed to control the laser focus during the crown preparation. Experiments are carried out with picosecond laser on wax resin and teeth. Results The accuracy of the system is satisfying, achieving the average linear errors of 0.06 mm for wax resin and 0.05 mm for dentin. The angle errors are 4.33° for wax resin and 0.5° for dentin. The depth errors for wax resin and dentin are both within 0.1 mm. The ablation time is 1.5 hours for wax resin and 3.5 hours for dentin. Conclusions The ablation experimental results show that the movement range and the resolution of the robotic system can meet the requirements of typical dental operations for tooth crown preparation. Also, the errors of tooth shape and preparation angle are able to satisfy the requirements of clinical crown preparation. Although the experimental results illustrate the potential of using picosecond lasers for 3D tooth crown preparation, many research issues still need to be studied before the system can be applied to clinical operations. Lasers Surg. Med. 46:573–581, 2014. © 2014 Wiley Periodicals, Inc.

Background Optimal selective photothermolysis of a pigment particle requires pulse durations equal to or less than the particle's thermal relaxation time (t½). Since tattoo particles in skin range in diameter from 40 to 300 nm, picosecond pulses would approximate t½ more closely and, therefore, might be more effective at tattoo particle fragmentation. Materials and Methods India Ink (carbon) or iron oxide tattoos were placed on the back of a Yorkshire pig. Six weeks later, each tattoo was treated with either a 758 nm 500 picosecond laser (Cynosure), a 755 nm 30–50 nanoseconds laser, or left untreated. After 4 weeks, clinical responses were evaluated by three dermatologists based on pre- and post-treatment photographs; histopathologic findings were evaluated by a dermatopathologist; and electron microscopic findings were analyzed for treated and non-treated carbon tattoos. Results After a single treatment, picosecond-domain pulses at 758 nm produced a significantly greater degree of carbon tattoo clearance compared to nanosecond-domain pulses at 755 nm. For iron oxide tattoos, both modalities produced minimal-to-poor clearance that was generally comparable. Neither modality resulted in scarring, textural changes, or hypopigmentation, and there was no histopathologic evidence of scarring. Electron micrographs revealed the presence of amorphous material (treated pigment) in picosecond and nanosecond laser-treated tattoos, consistent with effective targeting of India Ink pigment. Conclusions The 758 nm 500 picosecond laser is more effective at carbon tattoo clearance after one session in a porcine model than the 30–50 nanosecond laser emitting at a similar wavelength. Both lasers cleared carbon tattoos more effectively than iron oxide tattoos. Both lasers have a comparable safety profile, and neither produced clinical or histopathologic scarring. Further studies in humans are necessary to evaluate whether repeated treatments with picosecond versus nanosecond domain modalities might yield superior tattoo pigment clearance with a comparable safety profile. Lasers Surg. Med. 42:640–646, 2010. © 2010 Wiley-Liss, Inc.