Increased density was more likely to produce swelling, redness, and hyperpigmentation when compared to increased energy. Patient satisfaction is significantly higher when their skin is treated with high fluences, but not when patients' skin is treated with high densities.

Background and Objective: The role of pulsed dye laser (PDL) in the treatment of childhood hemangiomas is still controversial because of the inherent characteristics of hemangiomas as well as the side effects of the PDL. Recently, the long pulsed dye laser (LPDL) with cryogen spray cooling (CSC) has been found relatively more effective and safer than the PDL in the treatment of portwine stains and telangiectasia. This study was designed to compare the efficacy and complication rate of PDL versus LPDL for treating childhood hemangiomas. Study Design/Materials and Methods: We did a prospective, randomized, controlled trial in which we enrolled 52 Asian infants, aged 1-3 months, with early hemangiomas. These infants were assigned to PDL treatment (n ¼ 26) or LPDL treatment (n ¼ 26) and followed to age 1 year. A PDL with a wavelength of 585 nm and spot size of 7 mm and a LPDL with a wavelength of 595 nm and spot size of 7 mm were used. Each patient in the PDL group was treated with energy fluence between 6 and 7 J/cm 2 and a pulse duration of 0.45 milliseconds without epidermal cooling. Each patient in the LPDL group was treated with energy fluence between 9 and 15 J/cm 2 and a pulse duration of 10-20 milliseconds, utilizing CSC to protect the epidermis. Each group was treated at 4-week intervals until the lesion cleared. When each patient reached an age of 1 year, outcome measures such as clearance rate, time period of maximum proliferation, and complications were assessed. Results: The number of children whose lesions showed complete clearance or minimal residual signs at 1 year of age was 14 (54%) in the PDL group and 17 (65%) in the LPDL group (P ¼ 0.397). Compared with the LPDL, PDL treated children had more hypopigmentation (3, 12% vs. 8, 31%; P ¼ 0.001), more hyperpigmentation (2, 8% vs. 4, 15%; P ¼ 0.005), and more textural changes (1, 4% vs. 6, 23%; P ¼ 0.001). The average time period of maximum proliferation in the LPDL group was significantly shorter than that of the PDL group (106 days vs. 177 days; P ¼ 0.01). Conclusion: Early treatment of childhood hemangiomas with the LPDL is safer and more effective than the PDL.

High-density coverage fractional 1,927-nm thulium laser proved to be safe and effective for melasma with long-term remission.

Background: Leg veins can be effectively treated with lasers. However, the optimal pulse duration for small leg veins has not been established in human studies with a Nd:YAG laser. Objectives: The purpose of this study was to investigate a range of pulse durations to determine an optimal pulse duration for clearance of leg veins. Study Design/Materials and Methods: After mapping and photo documentation of the leg veins to be treated, a variable pulse duration Neodymium:Yttrium Aluminum Garnet (Nd:YAG) laser (3-100 milliseconds) was used in a single test site session. Pulse durations of 3, 20, 40, 60, 80, and 100 milliseconds were used. At the 3-week follow-up, the optimal pulse duration was defined as that pulse duration which resulted in the most complete clearance of vessels with the least side effects. Up to 20 vessels were then treated using the established ''optimal'' pulse duration. Final evaluation was at 16 weeks after the initial visit. Three blinded observers rated the percent of vessels completely cleared based on initial and final photographs. Results: Eighteen patients completed the study. Fluence thresholds for immediate vessel changes varied depending on spot size and vessel diameter, with larger fluences required for smaller spot sizes and smaller vessels. Shorter pulse durations ( 20 milliseconds) were associated with occasional spot sized purpura and spot sized post-inflammatory hyperpigmentation. Longer pulse durations (40-60 milliseconds) achieved superior vessel elimination with less post-inflammatory hyperpigmentation. With a single laser treatment, 71% of the treated vessels cleared. Conclusions: Compared to shorter pulses (<20 milliseconds), longer pulses may provide gentler heating of thevessel and a greater ratio of contraction to thrombosis.

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.