Prospective comparison study of a 550 picosecond 755 nm laser vs a 50 ns 755 nm laser in the treatment of nevus of Ota.

Since the introduction of selective photothermolysis, Q-switched nanosecond lasers have been used for the treatment of dermal pigmented lesions. Over the past several years, picosecond lasers have been introduced to the cosmetic community. We recently performed a study comparing a 550 picosecond 755 nm laser versus a 50 ns 755 nm laser, with the purpose of evaluating the clinical efficacy and complications of each laser when treating nevus of Ota. Ten Asian patients with nevus of Ota were enrolled in the study. Each lesion was split into 2 parts, and patients were treated with a 755 nm picosecond laser (PSL) and a 755 nm nanosecond laser (NSL). The clinical endpoint for fluence choice was immediate whitening (PSL: 2.33 ~ 3.36 J/cm2, NSL: 5.5 ~ 7 J/cm2) of the treated area. The pulse duration was fixed at 550 picoseconds (PSL) and 50 ns (NSL). The spot size of each laser was 2.5-3 mm. Laser treatments were performed until excellent clinical improvement was observed. Patients were examined 1 week after the first treatment, at each follow-up visit, and 6 months after the last laser treatment. The average number of treatment sessions to achieve excellent clinical improvement was 4.2 treatments using PSL and 5.4 treatments using NSL. One case of hyperpigmentation and one case of hypopigmentation were observed in the NSL treatment group. There were no complications in the PSL treatment group. The 755 nm 550 picosecond laser is significantly more effective than the 755 nm 50 ns laser in the treatment of nevus of Ota. The PSL treatment group also had minimum side effects.

Serious Adverse Events With Injectable Fillers: Retrospective Analysis of 7,659 Patient Outcomes.

BACKGROUND: In total, 2.7 million injectable filler treatments were performed in 2019 in the United States. Although generally considered to be a safe treatment modality, adverse events may occur in rare situations. OBJECTIVE: Analyze serious adverse events from injectable filler treatments, including infections, cutaneous necrosis, blindness, or delayed-onset nodule formation, spanning 11 years for 3 board-certified dermatologists and review their incidence, management, and outcomes. MATERIALS AND METHODS: A retrospective analysis was performed of injectable filler treatments spanning 11 years at a multipractitioner outpatient clinic. Serious adverse events were identified, and treatment measures were documented. A literature search was performed to determine recent trends and outcomes for comparison. RESULTS: Between January 2009 and August 2020, 18,013 mL of injectable filler was administered to 7,659 patients. Of the 18,013 mL administered, 74.1% comprised hyaluronic acid derivatives, 19.19% poly-l-lactic acid, and 6.71% calcium hydroxylapatite. Four serious adverse events were identified. Three events were delayed-onset skin nodule formation. One adverse event was related to vascular compromise and subsequent cutaneous necrosis. After appropriate treatment, all adverse events resolved without significant long-term sequelae. CONCLUSION: Serious adverse events associated with injectable fillers, when performed by board-certified dermatologists, are extremely rare and can be successfully managed with appropriate treatment.

Mechanism of crescent-shaped and ring-shaped epidermal damage from laser hair removal with cryogen spray cooling.

The safety and efficacy of laser hair removal have been well established through many clinical studies and through clinical use over the past 25 years. A laser hair removal device that protects the epidermis by utilizing cryogen spray cooling (CSC) is widely used internationally. In darker skin types, post-inflammatory hyperpigmentation (PIH) can occur after laser hair removal. In particular, laser hair removal with CSC is known to cause crescent-shaped or ring-shaped PIH. In this experiment, we report a visualization of this PIH mechanism. The laser used in this experiment is a 755-nm-long-pulsed alexandrite laser. Graph paper was treated with this laser to assess for thermal damage. We investigated changes in thermal damage due to differences in laser spot size, fluence output, and laser beam angle in relation to the graph paper. When using a spot size of 18 mm, we observed that higher fluences caused crescent-shaped thermal damage on the margins of the treated graph paper. It was also confirmed that when the hand piece is not held perpendicular to the skin, the laser-treated area is expanded and the CSC range is narrowed. These factors caused the area of thermal damage to widen. This widening causes ring-shaped thermal injury, leading to PIH. We treated graph paper using a hair removal laser with CSC to investigate the mechanism of crescent or ring-shaped thermal damage. Laser treatment on graph paper is effective as a test for defects in the CSC device. Factors that cause inadequate cooling, which leads to PIH, are large spot size, high fluence, not holding the laser hand piece perpendicular to the skin, and malfunctioning of CSC device.

Treatment of melasma with the 1,927-nm fractional thulium fiber laser: a retrospective analysis of 20 cases with long-term follow-up.

BACKGROUND: Melasma is a common acquired symmetrical hyperpigmentation that is often recurrent and refractory. OBJECTIVES: To investigate the efficacy and safety of a single administration of high-density fractional thulium fiber laser (1,927 nm) for the treatment of refractory melasma in 20 patients. MATERIALS AND METHODS: A retrospective chart and photographs review of 20 women (Fitzpatrick skin type II-IV) with clinical diagnosis of melasma treated with the 1,927-nm fractionated thulium laser at 10 or 20 mJ/cm(2) , with 60-70% surface area coverage. Four investigators independently evaluated Melasma Area Severity Index (MASI) scores before, 4 weeks, 3-6 months, and 6-12 months after treatment. RESULTS: Mean MASI scores decreased dramatically from 13.2 ± 5.4 before treatment to 8.5 ± 3.5 at 4 weeks after laser treatment (P = 0.004). Patient assessment revealed that 12 of the 20 subjects had more than 50% clearance of their melasma. Recurrence was reported by 7 out of 15 patients who were successfully followed-up (mean 10.2 months). Two patients developed postinflammatory hyperpigmentation that subsided with topical bleaching after 3 months. CONCLUSION: High-density coverage fractional 1,927-nm thulium laser proved to be safe and effective for melasma with long-term remission.

Split-face comparison study of cryogen spray cooling versus pneumatic skin flattening in skin tightening treatments using a long-pulsed Nd:YAG laser.

BACKGROUND: Nd:YAG pulsed lasers are used for non-ablative skin tightening treatment. A common drawback of this procedure is pain, which is often intolerable. Pneumatic skin flattening (PSF) is a new technology which alleviates pain in laser treatments. The purpose of this study is to assess the clinical efficacy and pain reduction in Nd:YAG laser skin tightening treatments with PSF compared to Nd:YAG laser skin tightening treatments with cryogen spray cooling (CSC). METHODS: Eleven patients were treated on the face with an Nd:YAG laser operated at an energy setting of 30 J/cm(2) and a pulse duration of 50 ms. Half of the face was treated with the Nd:YAG using CSC and the other side was treated with the Nd:YAG using PSF. A comparison of pain elicited from each treatment was done by comparing each patient's VAS pain scoring of the two sides. RESULTS: Treatment efficacy with CSC and with PSF was identical. The study confirmed significant pain reduction with PSF (p < 0.01). The average pain scores for PSF and CSC were 2.4 and 6.9, respectively. Mild ecchymosis was observed in two patients on the PSF side. CONCLUSION: Nd:YAG laser skin tightening treatments with PSF are less painful than Nd:YAG laser skin tightening treatments with CSC; the PSF treatments can be done with minimum side effects.

Prospective Comparison Study of 532/1064 nm Picosecond Laser vs 532/1064 nm Nanosecond Laser in the Treatment of Professional Tattoos in Asians.

BACKGROUND AND AIMS: Although, the pulse width should be shorter than the thermal relaxation time of the target, nanosecond laser pulses are not short enough for tattoo removal. Complications are common, such as hyper or hypopigmentation, textural changes, and scarring. Moreover, patients with darker skin types are at a higher risk of complications from tattoo removal using these lasers. Picosecond lasers were developed to overcome the limitation of nanosecond lasers. We did a comparison study of a 532/1064 nm picosecond laser vs a 532/1064 nm nanosecond laser to evaluate the clinical efficacy and complications of multi-color tattoos in Asians. MATERIALS AND METHODS: Eleven Asian patients with 37 professional tattoos were enrolled in the study. Each patient was treated with a 532/1064 nm nanosecond laser and a 532/1064 nm picosecond laser. The spot size that was used with each laser was 3 mm. Four treatments were performed, with four week intervals between each treatment. Patients were examined a week after the first treatment and 3 months after the last treatment. RESULTS AND CONCLUSIONS: All patients tolerated the treatments well. The efficacy of the 1064 nm picosecond laser for black tattoos is significantly better than the other studied lasers. The efficacy of the 532 nm picosecond laser is significantly better than the other studied lasers for red tattoos. The efficacy of the 532 nm picosecond laser is significantly better than the 532 nm nanosecond laser and better than the 1064 nm picosecond laser for green tattoos. Mild to moderate post-inflammatory hyperpigmentation was observed in 35.1%, 24.3% 27.0%, and 21.6% of the tattoos treated with the 532 nm nanosecond laser, the 532 nm picosecond laser, the 1064 nm nanosecond laser, and the 1064 nm pico-second laser, respectively. Paradoxical darkening (5.4%) was observed equally with each type of laser. There was no scar formation in any of the tattoos treated. The 532/1064 nm picosecond laser is more effective than the 532/1064 nm nanosecond laser in the treatment of multi-color tattoos in Asians. The 532 nm picosecond laser is more effective than 1064 nm picosecond laser in every tattoo color, with the exception of black. Paradoxical darkening was observed, even the use of picosecond lasers.

Treatment of traumatic scars using plasma skin regeneration (PSR) system.

OBJECTIVES: Several modalities have been advocated to treat traumatic scars, including surgical techniques and laser resurfacing. Recently, a plasma skin regeneration (PSR) system has been investigated. There are no reports on plasma treatment of traumatic scars. The objective of our study is to evaluate the effectiveness and complications of plasma treatment of traumatic scars in Asian patients. MATERIALS AND METHODS: Twenty Asian patients with traumatic scars were enrolled in the study. Three treatments were performed at monthly intervals with PSR, using energy settings of 2 to 3J. Patients were seen 1 week after each individual treatment and 3 months after the last treatment. Improvement was determined by patient questionnaires and physician evaluation of digital photographs taken prior to treatment and at 3 months post-treatment. The patients were also evaluated for any side effects from the treatment. RESULTS: Nine of 20 patients showed more than 50% improvement. The average pain score on a 10 point scale was 5.8+/-1.3 SD and all patients tolerated the treatments. The average re-epithelization time was 7.3+/-2.8 SD days. Temporary and local hyperpigmentation was observed in four patients and this hyperpigmentation disappeared within 3 months. Hypopigmentation and worsening of scarring were not observed. CONCLUSIONS: Plasma treatment is clinically effective and is associated with minimal complications when used to treat traumatic scars in Asian patients. However, deep traumatic scars are resistant to plasma treatment.

Long-pulsed neodymium:yttrium-aluminum-garnet laser treatment for hypertrophic port-wine stains on the lips.

Pulsed dye laser (PDL) treatment of hypertrophic port-wine stains (PWSs) on the lips has demonstrated poor efficacy and a potential risk of dyspigmentation. PDL-resistant hypertrophic PWS may require treatment with deeper penetrating lasers such as a 1064-nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser. The objective of this clinical study was to evaluate the efficacy and safety of a Nd:YAG laser for the treatment of hypertrophic PWSs on the lips. Ten patients (four were male and six were female) with hypertrophic PWSs on the lips were recruited in this study. Eight patients showed good to excellent improvement without complications. In conclusion, the Nd:YAG laser is safe and effective for treating hypertrophic PWSs on the lips.

Randomized, evaluator-blind, split-face comparison study of single cross-linked versus double cross-linked hyaluronic acid in the treatment of glabellar lines.

BACKGROUND At present, various hyaluronic acids are being used to rejuvenate facial skin. There is no comparative study of single cross-linked hyaluronic acid (SCHA) versus double cross-linked hyaluronic acid (DCHA). The objective of our study is to compare the effectiveness and complications of SCHA versus DCHA in the treatment of glabellar lines. METHODS Ten female patients were enrolled in this randomized, evaluator-blind study. One side (left vs. right) of each patient's glabellar lines was treated with SCHA and the other side was treated with DCHA. Two independent blinded observers reviewed the clinical photographs at 3, 6, 9, and 12 months after the treatment and assessed for degree of improvement as well as complications. RESULTS The two products were equally effective in producing an optimal cosmetic result, although at 6, 9, and 12 months posttreatment, a higher proportion of patients showed over 50% improvement with DCHA than with SCHA. At 12 months posttreatment, DCHA was considered superior in 70% of patients, whereas SCHA was superior in 10% of patients. CONCLUSIONS Both SCHA and DCHA are equally effective in producing an optimal cosmetic result. DCHA provides a more durable esthetic improvement when compared to SCHA in the treatment of glabellar lines.

Mongolian spots with involvement of mandibular area.

A 1-year-old boy had grayish pigmentation on the left side of his face over the area supplied by the mandibular branch of the trigeminal nerve. Upon further examination, the lesion was also found on the left side of the neck, shoulder, upper arm, right lower back and buttock. The pigmentation was uniform in intensity. This case report demonstrates that Mongolian spots can occur on the face in the area supplied by the mandibular branch of the trigeminal nerve. These spots should not be misdiagnosed as nevus of Ota.

Evaluation of fluence and pulse-duration on purpuric threshold using an extended pulse pulsed-dye laser in the treatment of port wine stains.

Laser therapy of port-wine stains (PWS) using the extended pulse pulsed-dye laser (EPPDL) is accepted as the optimal approach because the thermal relaxation time for the vessels in PWS is actually 1-10 msec. The purpose of this study is to elucidate the purpuric threshold using the EPPDL for treatment of PWS. One hundred and seventy-seven Japanese patients with PWS were recruited for this study. All the patients were dark-skinned with skin phototype III (n = 103) and IV (n = 74). PWS were treated with the EPPDL with a pulse duration ranging 1.5-10 msec, fluence ranging 9-15 J/cm(2), and a spot size of 7 mm. Cryogen spray cooling (CSC) was fixed to 30 msec of delay and 30 msec of spray duration. Patients returned to our clinic within 1 week after their initial laser therapy and the treatment sites were examined for the evidence of purpura formation. Of the 177 patients, 108 developed purpura. The lowest fluences that caused purpura and were seen in more than 50% of patients were 10 J/cm(2) with a pulse duration of 1.5 msec, 12 J/cm(2) with a pulse duration of 3 msec, 13 J/cm(2) with a pulse duration of 6 msec, and 13 J/cm(2) with a pulse duration of 10 msec. The fluence and pulse duration thresholds were 12.5 J/cm(2) and 1.65 msec, respectively. Because purpura is one of the treatment endpoints when using a pulsed-dye laser for PWS, higher fluences are necessary when using a long pulse duration.

Theoretical review of the treatment of pigmented lesions in Asian skin.

Asian skin has a higher epidermal melanin content, making it more likely to develop adverse pigmentary reactions following laser surgery. The nanosecond lasers are the gold standard for the treatment of pigmented lesions, but the risk of complications, such as post-inflammatory hyperpigmentation, is increased in dark-skinned patients. Intense Pulsed Light (IPL) or long-pulsed lasers are available for treating superficial pigmented lesions, and fewer complications are seen when using these devices compared to the nanosecond lasers. Nanosecond lasers are essential in the treatment of dermal melanosis. Recently, picosecond lasers have been investigated. Picosecond lasers will also play an important role in the treatment of pigmented lesions.

Multicenter prospective cohort study of the incidence of adverse events associated with cosmetic dermatologic procedures: lasers, energy devices, and injectable neurotoxins and fillers.

IMPORTANCE: Common noninvasive to minimally invasive cosmetic dermatologic procedures are widely believed to be safe given the low incidence of reported adverse events, but reliable incidence data regarding adverse event rates are unavailable to date. OBJECTIVE: To assess the incidence of adverse events associated with noninvasive to minimally invasive cosmetic dermatologic procedures, including those involving laser and energy devices, as well as injectable neurotoxins and fillers. DESIGN, SETTING, AND PARTICIPANTS: A multicenter prospective cohort study (March 28, 2011, to December 30, 2011) of procedures performed using laser and energy devices, as well as injectable neurotoxins and soft-tissue augmentation materials, among 8 geographically dispersed US private and institutional dermatology outpatient clinical practices focused on cosmetic dermatology, with a total of 23 dermatologists. Participants represented a consecutive sample of 20 399 cosmetic procedures. Data acquisition was for 3 months (13 weeks) per center, with staggered start dates to account for seasonal variation. EXPOSURES: Web-based data collection daily at each center to record relevant procedures, by category type and subtype. Adverse events were detected by (1) initial observation by participating physicians or staff; (2) active ascertainment from patients, who were encouraged to self-report after their procedure; and (3) follow-up postprocedural phone calls to patients by staff, if appropriate. When adverse events were not observed by physicians but were suspected, follow-up visits were scheduled within 24 hours to characterize these events. Detailed information regarding each adverse event was entered into an online form. MAIN OUTCOMES AND MEASURES: The main outcome was the total incidence of procedure-related adverse events (total adverse events divided by total procedures performed), as verified by clinical examination. RESULTS: Forty-eight adverse events were reported, for a rate of 0.24% (95% CI, 0.18%-0.31%). Overall, 36 procedures resulted in at least 1 adverse event, for a rate of 0.18% (95% CI, 0.13%-0.25%). No serious adverse events were reported. Adverse events were infrequently associated with known risk factors. CONCLUSIONS AND RELEVANCE: Noninvasive to minimally invasive cosmetic dermatologic procedures, including energy, neurotoxin, and filler procedures, are safe when performed by experienced board-certified dermatologists. Adverse events occur in less than 1% of patients, and most of these are minor and transient.

Treatment of mesh skin grafted scars using a plasma skin regeneration system.

Objectives. Several modalities have been advocated to treat traumatic scars, including surgical techniques and laser resurfacing. Recently, a plasma skin regeneration (PSR) system has been investigated. There are no reports on plasma treatment of mesh skin grafted scars. The objective of our study is to evaluate the effectiveness and complications of plasma treatment of mesh skin grafted scars in Asian patients. Materials and Methods. Four Asian patients with mesh skin grafted scars were enrolled in the study. The plasma treatments were performed at monthly intervals with PSR, using energy settings of 3 to 4 J. Improvement was determined by patient questionnaires and physician evaluation of digital photographs taken prior to treatment and at 3 months post treatment. The patients were also evaluated for any side effects from the treatment. Results. All patients showed more than 50% improvement. The average pain score on a 10-point scale was 6.9 +/- 1.2 SD and all patients tolerated the treatments. Temporary, localized hypopigmentation was observed in two patients. Hyperpigmentation and worsening of scarring were not observed. Conclusions. Plasma treatment is clinically effective and is associated with minimal complications when used to treat mesh skin grafted scars in Asian patients.

Fractional carbon dioxide laser and plasmakinetic skin resurfacing.

Photodamage is one of the most common reasons that patients visit a dermatologist's office. Carbon dioxide (CO(2)) laser resurfacing has always been the gold standard for reversing photodamage. Because of the relatively high incidence of side effects and the prolonged downtime associated with CO(2) resurfacing, new technologies have emerged to address photodamage. Portrait skin regeneration (PSR) is a novel device that has been developed to treat photodamage, and this device yields fewer side effects and downtime than traditional CO(2) laser resurfacing. At our center, we have performed more than 500 high-energy PSR treatments and have developed a unique and highly effective treatment protocol. In addition, fractional CO(2) laser resurfacing has emerged as the latest technology developed to combat photoaging. This technology yields impressive results and is much safer and causes less downtime than traditional CO(2) laser resurfacing. In this article, we will review our treatment techniques and protocols as well as address patient selection, preoperative and postoperative care, and anesthesia.

Comparison study of a long-pulse pulsed dye laser and a long-pulse pulsed alexandrite laser in the treatment of port wine stains.

BACKGROUND: Port wine stains (PWSs) are commonly treated by the pulsed dye laser. Recently, a long-pulse pulsed alexandrite laser was used to treat bulky vascular malformations. OBJECTIVE: In the present study, we compare the efficacy and complications of the long-pulse pulsed dye laser (LPPDL) and the long-pulse pulsed alexandrite laser (LPPAL) in the treatment of PWSs. METHODS: Eleven patients with Fitzpatrick skin types III-IV were enrolled in this study. One section of each patient's PWS was treated with LPPDL and another section was treated with LPPAL. The patients' PWSs were evaluated for efficacy of elimination of erythema and for treatment-related side effects. RESULTS: Both LPPDL and LPPAL treatment are effective in the treatment of PWSs. Hyperpigmentation was seen in two areas treated with LPPDL and in three areas treated with LPPAL. Hypopigmentation was seen in one area treated with LPPAL, but not in any of the areas treated with LPPDL. There was no scarring. CONCLUSION: LPPAL works best with hypertrophic, purple PWSs, while LPPDL yields better clinical improvements with the flat, pink PWSs. Targeting of deoxyhemoglobin, deeper penetration, and higher fluence may explain the effectiveness of LPPAL in purple, hypertrophic PWSs. However, there is a risk of dyspigmentation when using the LPPAL.

Comparison study of intense pulsed light versus a long-pulse pulsed dye laser in the treatment of facial skin rejuvenation.

Currently, various nonablative skin resurfacing techniques are being used to rejuvenate facial skin, including lasers and intense pulsed light (IPL). There are few direct comparison studies between IPLs and lasers. The objective of our study is to compare the effectiveness of intense pulsed light versus a long-pulse pulsed dye laser (LPDL) in the treatment of facial skin rejuvenation. Ten Asian patients with Fitzpatrick skin types III-IV were enrolled in this study. One half of the face was treated with IPL (6 treatment sessions) and the other side was treated by LPDL (3 treatment sessions). An LPDL with a wavelength of 595 nm and spot size of 7 mm was used. Utilizing the compression method, lentigines were treated using a PDL with a fluence between 9-12 J/cm and a pulse duration of 1.5 ms. Wrinkles were treated with fluences between 10 to 12 J/cm and a pulse duration of 20 ms, using a pulse-stacking technique. An IPL with a type B handpiece was used. Lentigines and wrinkles were treated with fluences between 27 to 40 J/cm and a pulse duration of 20 ms. The improvement of lentigines was 62.3% and 81.1% for IPL and LPDL respectively. There was no significant difference between IPL and LPDL in wrinkle reduction. There was no scarring or pigmentary change seen with either device. Both IPL and LPDL are effective for facial skin rejuvenation in Asians, but LPDL treatment is significantly better than IPL treatment in the treatment of lentigines. The use of the compression technique may allow this LPDL to be used effectively for facial rejuvenation and with fewer treatment sessions, when compared with the IPL.

Treatment of resistant port-wine stains with a variable-pulse pulsed dye laser.

BACKGROUND: The conventional pulsed dye laser (PDL), operating at a wavelength of 585 nm and a pulse duration of 0.45 ms, usually does not achieve complete clearance in the majority of port-wine stains (PWSs). OBJECTIVE: In this study, we demonstrate the efficacy of a variable-pulse pulsed dye laser (VPPDL) equipped with cryogen spray cooling (CSC) in the treatment of PWS that have become resistant to PDL treatment. METHODS: Forty Asian patients with Fitzpatrick skin types III to IV were enrolled in this study. All patients had previously been treated by the PDL at least eight times (mean, 12.8+/-5.9) and had reached a treatment plateau. A VPPDL with a wavelength of 595 nm and a spot size of 7 mm was used. The patients were treated with fluences between 9 and 15 J/cm(2) and pulse durations of 1.5 to 10 ms. Four treatments were administered at 8-week intervals for each lesion. Three months after the last treatment, all patients were evaluated for the degree of improvement by two independent clinicians. RESULTS: Eight patients had excellent improvement, 9 had good improvement, 11 had fair improvement, and 12 had poor improvement. No complications were observed during the course of laser treatment. Vessels larger than 30 microm were not seen in the biopsy specimens obtained after the final treatment. CONCLUSION: The VPPDL is more effective than the PDL and the VPPDL should be used for treating PDL-resistant PWSs. Nonetheless, vessels less than 30 mum in diameter are resistant to both PDL and VPPDL treatment.

Comparison study of a Q-switched alexandrite laser delivered with versus without compression in the treatment of dermal pigmented lesions.

BACKGROUND: The Q-switched laser is the treatment of choice when attempting to improve dermal pigmented lesions. However, purpura and dyspigmentation are frequently observed after treatment. OBJECTIVE: To compare the efficacy and complications of the Q-switched alexandrite laser when delivered with versus without compression in the treatment of dermal pigmented lesions. METHODS: Ten patients with dermal lesions were enrolled in the study. Each patient had a lesion treated with the Q-switched alexandrite laser delivered with compression. Each patient also had a lesion treated with the Q-switched alexandrite laser delivered without compression with the same fluence and spot size. The patients were evaluated for efficacy and treatment-related side effects. RESULTS: There was no significant difference in efficacy, but purpura and dyspigmentation were more likely when pigmented lesions were treated without compression. CONCLUSION: Purpura from Q-switched laser treatment in darkly pigmented skin is due to mechanical injury of blood vessels. It is well known that pressure 'diascopy' eliminates blood from cutaneous vessels by coapting the vessel lumen. In this study, we used pressure applied by a glass window on the Q-switched laser handpiece to remove cutaneous blood during laser exposure, making it possible to reduce purpura and dyspigmentation.

Long-pulse pulsed dye laser delivered with compression for treatment of facial lentigines.

BACKGROUND AND OBJECTIVE: The 595-nm long-pulsed dye laser (LPDL) has been used for the treatment of vascular lesions, and although it is well absorbed by blood, it is also well absorbed by melanin. To utilize this device for the treatment of facial lentigines, we attached a glass window to the tip of the laser's handpiece, allowing compression of the skin during treatment. This prospective study aims to evaluate the efficacy and complications of using a LPDL delivered with compression for the treatment of facial lentigines in Asian persons. MATERIALS AND METHODS: Fifty-four Asian patients with facial lentigines were enrolled in this study. The laser settings included fluences between 9 and 13 J/cm(2) and a constant pulse duration of 1.5 ms. Cryogen spray cooling was not used. RESULTS: Thirty-eight patients showed excellent results, 14 patients showed good results, and 2 patients showed fair results. Hyperpigmentation was seen in 1 patient. CONCLUSION: LPDL delivered with the compression method is effective in the treatment of facial lentigines in Asian patients, and the side effect profile is minimal. The compression technique allows the traditional "vascular" LPDL to be used for treating a variety of pigmented lesions.