From the Ichan School of Medicine at Mount Sinai, New York, New York.
Supported by the Geoffrey Dowling Fellowship, a grant from the British Association of Dermatologists (United Kingdom). Dr. Mansouri reports no conflict of interest. Dr. Goldenberg is a consultant and investigator for Bayer Health Care Pharmaceuticals and is a speaker for Galderma Laboratories, LP.
Correspondence: Gary Goldenberg, MD, Department of Dermatology, Mount Sinai Hospital, 5 E 98th St, 5th Floor, New York, NY 10029-6574 (garygoldenbergmd@gmail.com).
Although newer-generation PDLs still have the potential to cause purpura, various attempts have been made to minimize this risk, such as the use of longer pulse durations, multiple minipulses or “pulselets,”13 and multiple passes. Separate parameters may need to be used when treating linear vessels and diffuse erythema, with longer pulse durations required for larger vessels. The Figure shows a rosacea patient with facial telangiectasia before and after 1 treatment with a PDL.
Facial telangiectasia in a rosacea patient before (A) and after 1 treatment with a pulsed dye laser (B).
According to Alam et al,14 purpuric settings were more efficacious in a comparison of variable-pulsed PDLs for facial telangiectasia. In 82% (9/11) of cases, greater reduction in telangiectasia density was noted on the side of the face that had been treated with purpuric settings versus the other side of the face.14 Purpuric settings are particularly effective in treating larger vessels, while finer telangiectatic vessels may respond to purpura-free settings.
In a study of 12 participants treated with a 595-nm PDL at a pulse duration of 6 ms and fluences from 7 to 9 J/cm2, no lasting purpura was seen; however, while 9 participants achieved more than 25% improvement after a single treatment, only 2 participants achieved more than 75% improvement.15 Nonetheless, some patients may prefer this potentially less effective treatment method to avoid the socially embarrassing side effect of purpura.
In a study of 12 rosacea patients, a 75% reduction in telangiectasia scores was noted after a mean of 3 treatments with the 585-nm PDL using 450-ms pulse durations. Purpura occurred in all patients.16 In another study by Madan and Ferguson,17 18 participants with nasal telangiectasia that had been resistant to the traditional round spot, 595-nm PDL and/or 532-nm KTP laser were treated with a 3x10-mm elliptical spot, ultra-long pulse, 595-nm PDL with a 40-ms pulse duration and double passes. Complete clearance was seen in 10 (55.6%) participants and 8 (44.4%) showed more than 80% improvement. No purpura was associated with the treatment.17
Further studies comparing the efficacy of nonpurpuric and purpuric settings in the same patient would allow us to determine the most effective option for future treatment.
KTP Laser (532 nm)
Potassium titanyl phosphate lasers have the disadvantage of higher melanin absorption, which can lead to epidermal damage with postinflammatory hyperpigmentation. Their use is limited to lighter skin types. Because of its shorter wavelength, the KTP laser is best used to treat superficial telangiectasia. The absence of posttreatment purpura can make KTP lasers a popular alternative to PDLs.17 Uebelhoer et al18 performed a split-face study in 15 participants to compare the 595-nm PDL and 532-nm KTP laser. Although both treatments were effective, the KTP laser achieved 62% clearance after the first treatment and 85% clearance 3 weeks after the third treatment compared to 49% and 75%, respectively, for the PDL. Interestingly, the degree of swelling and erythema posttreatment were greater on the KTP laser–treated side.18
Nd:YAG (1064 nm)
The wavelength of the Nd:YAG laser targets the lower absorption peak of oxyhemoglobin. In a study of 15 participants with facial telangiectasia who were treated with a 1064-nm Nd:YAG laser at day 0 and day 30 using a 3-mm spot size, a fluence of 120 to 170 J/cm,2 and 5- to 40-ms pulse durations, 73% (11/15) showed moderate to significant improvement at day 0 and day 30 and 80% improvement at 3 months’ follow-up.19 In a split-face study of 14 patients, treatment with the 595-nm PDL with a fluence of 7.5 J/cm2, pulse duration of 6 ms, and spot size of 10 mm was compared with the 1064-nm Nd:YAG laser with a fluence of 6 J/cm2, pulse duration of 0.3 ms, and spot size of 8 mm.20 Erythema improved by 6.4% from baseline on the side treated with the PDL. Although participants rated the Nd:YAG laser treatment as less painful, they were more satisfied with the results of the PDL treatment.20 In another split-face study comparing the 595-nm PDL and 1064-nm Nd:YAG laser, greater improvement was reported with the Nd:YAG laser, though the results were not statistically significant.21
Intense Pulsed Light
While lasers use selective photothermolysis, IPL devices emit noncoherent light at a wavelength of 500 to 1200 nm. Cutoff filters allow for selective tissue damage depending on the absorption spectra of the tissue. Longer wavelengths are effective for the treatment of deeper vessels, while shorter wavelengths target more superficial vessels; however, the shorter wavelengths can interact with melanin and should be avoided in darker skin types. In a phase 3 open trial, 34 participants were treated with IPL with a 560-nm cutoff filter and fluences of 24 to 32 J/cm2. The mean reduction of erythema following 4 treatments was 39% on the cheeks and 22% on the chin; side effects were minimal.22
